cFIREsim has been revised and is super easy to use.

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rgs92
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cFIREsim has been revised and is super easy to use.

Post by rgs92 »

I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
Last edited by rgs92 on Sat Mar 27, 2021 9:07 pm, edited 3 times in total.
Silk McCue
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Re: Cfiresim has been revised and is super easy to use.

Post by Silk McCue »

Thanks for sharing.

Cheers
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Re: Cfiresim has been revised and is super easy to use.

Post by edgeagg »

I still prefer the portfolio visualizer simulation that lets me model sequence of returns risk.
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rgs92
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Re: Cfiresim has been revised and is super easy to use.

Post by rgs92 »

Sure, port-vis, i-orp, and even full Firecalc itself are more comprehensive, but this was an alert for those who might not normally do their own analysis because they are nervous about complexity or difficulty, and still want something that provides a good handle of where they stand for retirement without having to ask an adviser (or anyone for that matter).

It should be a first step before even asking here. Previously, it was a bit clunky and confusing. But it's much more comprehensive and thorough than the extremely simple ones on the major financial sites.
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Re: Cfiresim has been revised and is super easy to use.

Post by Dottie57 »

Cfiresim is more optimistic than firecalc.
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rgs92
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Re: Cfiresim has been revised and is super easy to use.

Post by rgs92 »

Dottie57 wrote: Fri Mar 12, 2021 11:11 am Cfiresim is more optimistic than firecalc.
Interesting. I was under the impression that they were both based on the same underlying historical data and used the same algorithm and formulas when based on the same input data. So I'd be curious about why this is true. Thanks for the heads-up Dottie. I appreciate it.
[edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
Last edited by rgs92 on Fri Mar 12, 2021 11:59 am, edited 3 times in total.
Marseille07
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Re: Cfiresim has been revised and is super easy to use.

Post by Marseille07 »

Thanks for sharing, this is good stuff.
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Re: Cfiresim has been revised and is super easy to use.

Post by Dottie57 »

rgs92 wrote: Fri Mar 12, 2021 11:36 am
Dottie57 wrote: Fri Mar 12, 2021 11:11 am Cfiresim is more optimistic than firecalc.
Interesting. I was under the impression that they were both based on the same underlying historical data and used the same algorithm and formulas when based on the same input data. So I'd be curious about why this is true. Thanks for the heads-up Dottie. I appreciate it.
[edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
I am not sure if cfiresim is simply a front end. I like Firecalc because I can tweak it for different rates of return and inflation rates.
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Re: Cfiresim has been revised and is super easy to use.

Post by JoeRetire »

Dottie57 wrote: Fri Mar 12, 2021 2:41 pm I am not sure if cfiresim is simply a front end. I like Firecalc because I can tweak it for different rates of return and inflation rates.
Have you realized that cfiresum can be tweaked for different rates of return and inflation?
It's the end of the world as we know it. | It's the end of the world as we know it. | It's the end of the world as we know it. | And I feel fine.
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Re: Cfiresim has been revised and is super easy to use.

Post by Dottie57 »

JoeRetire wrote: Fri Mar 12, 2021 6:51 pm
Dottie57 wrote: Fri Mar 12, 2021 2:41 pm I am not sure if cfiresim is simply a front end. I like Firecalc because I can tweak it for different rates of return and inflation rates.
Have you realized that cfiresum can be tweaked for different rates of return and inflation?
Hmmm I will look further.
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Re: Cfiresim has been revised and is super easy to use.

Post by lauren_knows »

rgs92 wrote: Fri Mar 12, 2021 11:36 am
Dottie57 wrote: Fri Mar 12, 2021 11:11 am Cfiresim is more optimistic than firecalc.
Interesting. I was under the impression that they were both based on the same underlying historical data and used the same algorithm and formulas when based on the same input data. So I'd be curious about why this is true. Thanks for the heads-up Dottie. I appreciate it.
[edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
They are based on the same underlying data, but long story short: cFIREsim calculates bond returns based on the 10 year long interest rate slightly more accurately than Firecalc, based on some extensive conversations with users on this forum (namely LongInvest).

Source: I am the creator/maintainer of cFIREsim :)
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

rgs92 wrote: Fri Mar 12, 2021 8:31 am
As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.
Thank you for those kind words! (I created/maintain cFIREsim). It's really hard to wrangle a giant form with THAT many data inputs, to make it look good and make it easy to use. I am really trying to work on some good tutorial pages, because I know that is lacking at the moment.

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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rgs92
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by rgs92 »

Wow, that's awesome. It's an honor to respond to you.
If I was a hiring manager at a FAANG company I'd recruit you in a heartbeat.
The ability to distill useful information into a clear interactive format that is easy to use and understand is rare talent. cFiresim is real work of art.
Best of luck.
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Re: Cfiresim has been revised and is super easy to use.

Post by lauren_knows »

rgs92 wrote: Fri Mar 12, 2021 11:36 am [edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
Just to clarify, this is 100% not true. It is completely stand-alone.

I originally made it in 2013 because of the lack of flexibility in Firecalc's inputs (namely you couldn't add any (or many) custom spending or income/savings adjustments that had variable year ranges. For instance, I always set myself up with a base yearly spending, and have 2 separate 4-yr spans where I'm paying kids college tuition in the future. Then another input for when we might sell the house and downsize. Then another for internal company stock sale when I retire. Then another for the start of my wife's pension. etc etc.

At the time, there were also a lot of users clamoring for other features, but it was clear that the maintainer of Firecalc was just running the forum, and the real creator had retired to a sailboat somewhere :D
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by liberty53 »

Great tool and thanks for putting in so much hard work on it.

I did enjoy the previous versions ability to persist a simulation. I guess that feature may have been too expensive to maintain. Any chance it might come back in some way?
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

liberty53 wrote: Wed Mar 17, 2021 7:05 am Great tool and thanks for putting in so much hard work on it.

I did enjoy the previous versions ability to persist a simulation. I guess that feature may have been too expensive to maintain. Any chance it might come back in some way?
It still persists in a way. If you run a simulation, at the top of the output screen it gives you a link that will bring you back to the same inputs. Not quite as easy as a login with a list of saved items, but it's easier to maintain.
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Re: Cfiresim has been revised and is super easy to use.

Post by CyclingDuo »

boknows wrote: Tue Mar 16, 2021 10:01 pm
rgs92 wrote: Fri Mar 12, 2021 11:36 am
Dottie57 wrote: Fri Mar 12, 2021 11:11 am Cfiresim is more optimistic than firecalc.
Interesting. I was under the impression that they were both based on the same underlying historical data and used the same algorithm and formulas when based on the same input data. So I'd be curious about why this is true. Thanks for the heads-up Dottie. I appreciate it.
[edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
They are based on the same underlying data, but long story short: cFIREsim calculates bond returns based on the 10 year long interest rate slightly more accurately than Firecalc, based on some extensive conversations with users on this forum (namely LongInvest).

Source: I am the creator/maintainer of cFIREsim :)
Great job and excellent work. Thank you so much for the effort and the update.

CyclingDuo
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by liberty53 »

boknows wrote: Wed Mar 17, 2021 10:07 am
liberty53 wrote: Wed Mar 17, 2021 7:05 am Great tool and thanks for putting in so much hard work on it.

I did enjoy the previous versions ability to persist a simulation. I guess that feature may have been too expensive to maintain. Any chance it might come back in some way?
It still persists in a way. If you run a simulation, at the top of the output screen it gives you a link that will bring you back to the same inputs. Not quite as easy as a login with a list of saved items, but it's easier to maintain.
Oh - fantastic - didn't realize that. And it makes a lot of sense from an architecture point of view. Thanks!

Just thought - I wonder how many of us have nearly identical or very close simulation inputs? Could be some very useful data.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

liberty53 wrote: Wed Mar 17, 2021 10:34 am
boknows wrote: Wed Mar 17, 2021 10:07 am
liberty53 wrote: Wed Mar 17, 2021 7:05 am Great tool and thanks for putting in so much hard work on it.

I did enjoy the previous versions ability to persist a simulation. I guess that feature may have been too expensive to maintain. Any chance it might come back in some way?
It still persists in a way. If you run a simulation, at the top of the output screen it gives you a link that will bring you back to the same inputs. Not quite as easy as a login with a list of saved items, but it's easier to maintain.
Just thought - I wonder how many of us have nearly identical or very close simulation inputs? Could be some very useful data.
Yeah, it's a very interesting question. I could probably do a SQL query to figure out average Portfolio, Annual Spending, Social Security, etc.
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Re: Cfiresim has been revised and is super easy to use.

Post by Marseille07 »

lauren_knows wrote: Tue Mar 16, 2021 10:01 pm
rgs92 wrote: Fri Mar 12, 2021 11:36 am
Dottie57 wrote: Fri Mar 12, 2021 11:11 am Cfiresim is more optimistic than firecalc.
Interesting. I was under the impression that they were both based on the same underlying historical data and used the same algorithm and formulas when based on the same input data. So I'd be curious about why this is true. Thanks for the heads-up Dottie. I appreciate it.
[edit: I actually thought it was simply a front-end to Firecalc, and relayed your input data right into Firecalc. Is this not the case? Thanks again.]
They are based on the same underlying data, but long story short: cFIREsim calculates bond returns based on the 10 year long interest rate slightly more accurately than Firecalc, based on some extensive conversations with users on this forum (namely LongInvest).

Source: I am the creator/maintainer of cFIREsim :)
I'm a big fan of cFIREsim, thank you for developing it. Imo it's the best, much better than other services often mentioned around here.
iskey
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by iskey »

How do I account for a spouse who will be retiring in a different year than me, since there is only one set of inputs for retirement years? Do I need to run two separate simulations?

Thanks!
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

iskey wrote: Wed Mar 17, 2021 12:01 pm How do I account for a spouse who will be retiring in a different year than me, since there is only one set of inputs for retirement years? Do I need to run two separate simulations?

Thanks!
I would personally do it this way:

- Combine all investments into a single "Starting Portfolio" number and allocation percentages
- Combine all of your baseline spending into a single "Starting Annual Spending"
- Your "Retirement Start Year" is just when the simulation starts subtracting your spending from the portfolio. I would set this for whichever of you retires first
- Then add "Income/Savings" adjustments down below to simulate your pre-retirement contributions. You can have one amount and time period for you and your spouses combined contributions leading up to retirement, one amount and time period representing the time when one of you is retired, then any more after that.

You just need to keep in mind that once the "Retirement Start Date" hits, Spending gets taken out. So if your spending is $60k/yr, but your spouse still has a take-home of $80k/yr, you can add "80k per year" as an income/savings data point and it will effectively work out to "we're investing $20k per year while one person works, instead of whatever we were before"

Make sense?
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iskey
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by iskey »

lauren_knows wrote: Wed Mar 17, 2021 12:39 pm
iskey wrote: Wed Mar 17, 2021 12:01 pm How do I account for a spouse who will be retiring in a different year than me, since there is only one set of inputs for retirement years? Do I need to run two separate simulations?

Thanks!
I would personally do it this way:

- Combine all investments into a single "Starting Portfolio" number and allocation percentages
- Combine all of your baseline spending into a single "Starting Annual Spending"
- Your "Retirement Start Year" is just when the simulation starts subtracting your spending from the portfolio. I would set this for whichever of you retires first
- Then add "Income/Savings" adjustments down below to simulate your pre-retirement contributions. You can have one amount and time period for you and your spouses combined contributions leading up to retirement, one amount and time period representing the time when one of you is retired, then any more after that.

You just need to keep in mind that once the "Retirement Start Date" hits, Spending gets taken out. So if your spending is $60k/yr, but your spouse still has a take-home of $80k/yr, you can add "80k per year" as an income/savings data point and it will effectively work out to "we're investing $20k per year while one person works, instead of whatever we were before"

Make sense?
Got it, that does make sense. Thanks for the detailed response!
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by cockersx3 »

lauren_knows wrote: Wed Mar 17, 2021 10:48 am
liberty53 wrote: Wed Mar 17, 2021 10:34 am
boknows wrote: Wed Mar 17, 2021 10:07 am
liberty53 wrote: Wed Mar 17, 2021 7:05 am Great tool and thanks for putting in so much hard work on it.

I did enjoy the previous versions ability to persist a simulation. I guess that feature may have been too expensive to maintain. Any chance it might come back in some way?
It still persists in a way. If you run a simulation, at the top of the output screen it gives you a link that will bring you back to the same inputs. Not quite as easy as a login with a list of saved items, but it's easier to maintain.
Just thought - I wonder how many of us have nearly identical or very close simulation inputs? Could be some very useful data.
Yeah, it's a very interesting question. I could probably do a SQL query to figure out average Portfolio, Annual Spending, Social Security, etc.
I would definitely be interested in seeing the aggregated data for portfolio size, spending, percent success, etc just to see where my numbers stand relative to the average user. (Of course, I would assume that the "average user" of cFireSim would be a bit more financially literate that the average person, but would still be interesting.)

Of course, about 100 or so of those sims would be me, so there's that :D

It's a great tool by the way - made even better by the recent updates. One of the most user-friendly tools like this out there IMO. Thanks again for all the work on this!
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by Greg in Idaho »

lauren_knows wrote: Wed Mar 17, 2021 12:39 pm
iskey wrote: Wed Mar 17, 2021 12:01 pm How do I account for a spouse who will be retiring in a different year than me, since there is only one set of inputs for retirement years? Do I need to run two separate simulations?

Thanks!
I would personally do it this way:

- Combine all investments into a single "Starting Portfolio" number and allocation percentages
- Combine all of your baseline spending into a single "Starting Annual Spending"
- Your "Retirement Start Year" is just when the simulation starts subtracting your spending from the portfolio. I would set this for whichever of you retires first
- Then add "Income/Savings" adjustments down below to simulate your pre-retirement contributions. You can have one amount and time period for you and your spouses combined contributions leading up to retirement, one amount and time period representing the time when one of you is retired, then any more after that.

You just need to keep in mind that once the "Retirement Start Date" hits, Spending gets taken out. So if your spending is $60k/yr, but your spouse still has a take-home of $80k/yr, you can add "80k per year" as an income/savings data point and it will effectively work out to "we're investing $20k per year while one person works, instead of whatever we were before"

Make sense?
Longtime fan and user of cfiresim with this question...thank you so very much for the work you have put into it, including the recent updates/revitalization, and the above strategy for its use. Still my favorite tool for modeling possibilities...
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by ljford7 »

I have been playing around with it and really like it. Couple of questions/observations.

I think it needs a little bit of guidance on the questions (see below):

1. Under Basics: Does the Portfolio Value $: need to equal how much the portfolio should be in the retirement year, or is it how much the portfolio is today? This is a big issue that affects the outcome greatly. If you look at the results (Average Portfolio at Retirement), it should be the portfolio amount today and not at the retirement age.
2. Under Basics: Same question as above for the Initial Yearly Spending.
2. Under Basics: It would be helpful to have the option to put in ages in lieu of using retirement years (especially for people trying to retire early).

Once again, thank you for doing this.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

Let me preface my answer by saying that I'm in the middle of writing a LOT of tutorials and use-case scenarios to make a lot of this way more clear. I think I will have the first of these tutorials up by the weekend.
ljford7 wrote: Thu Mar 18, 2021 8:09 am
1. Under Basics: Does the Portfolio Value $: need to equal how much the portfolio should be in the retirement year, or is it how much the portfolio is today? This is a big issue that affects the outcome greatly. If you look at the results (Average Portfolio at Retirement), it should be the portfolio amount today and not at the retirement age.
"Portfolio Value $" is ALWAYS what you have in your portfolio today. If you are retiring in the future, you would additionally add an Adjustment down below (an income/savings adjustment) that would tell how much "contributions" you're adding to the portfolio every year, and set the End Date to your retirement start year. Here's a super simple example of that in action. Base scenario, except they retire in 2030, their current portfolio is only $500k, and they are contributing $25k per year up until retirement: https://www.cfiresim.com/886be286-2dea- ... 2c2699968d
2. Under Basics: Same question as above for the Initial Yearly Spending.
2. Under Basics: It would be helpful to have the option to put in ages in lieu of using retirement years (especially for people trying to retire early).
Spending is always the spending IN retirement. You list it in Today's Dollars, but it doesn't get taken out of your portfolio until retirement starts.

Hope this helps!

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by birdog »

Wow! This thing tells me I'm going to be rich! Rich, I tell you!!! Muuuuu uuuuuu haaaaa!!!!

This provided the most optimistic projections I've seen.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by nigel_ht »

Lauren,

Nice job. I've never actually used it before but the new iteration is nice and clean. I am curious that 60/40, 0 fees and 4% SWR results in 5 failures for a retirement starting 2021 and ending 2050. They are all in the expected 1964-1969 range but I had thought there were only 2 years where it failed (1965 and 1966). Oddly, it reports 5 failures but the Single Portfolio Dips shows 6 instances of $0 results. 1964 was in cycle 29 so maybe it doesn't count?

https://www.cfiresim.com/d0846f44-027a- ... 7e16273e8e

A rough approximation of Golden Butterfly 40/40/20 results in 5 reported failures but 9 zero dollar results. Looks like the same pattern...failures in the last year don't count which I guess is okay but I'm assuming that in many of these you didn't get the full $40K for that year.

https://www.cfiresim.com/d5e1351d-49c7- ... f29629cf97
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Re: Cfiresim has been revised and is super easy to use.

Post by nigel_ht »

edgeagg wrote: Fri Mar 12, 2021 9:11 am I still prefer the portfolio visualizer simulation that lets me model sequence of returns risk.
Thanks...I've never tried that before. I've only run backtests because generally I want to see how different AA's work out on the same chart.

Putting the worst 10 years up front really craters results...I can get around 3.6% SWR out of golden butterfly but the three fund at 40 US, 20 Ex-US and 40 bond is around 2.3% in that scenario.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by Grogs »

This is really cool. I like the input format a lot better than Firecalc since everything is on one tab. I always miss something when I try to do a bunch of Firecalc runs. I also like the 'Investigation Options' that automatically solves for the max. withdrawal to achieve a set level of success. The output plots are really informative too. It's interesting to see how all the really high values come from a couple of decades (1870s and 1920s for the most part).

One thing for adding additional income/savings, it would be nice to have a box with 'end at retirement' instead of having to separately adjust the end date each time. A similar option 'Start at retirement' might be useful for pensions.

Thanks for the hard work on this. :sharebeer
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by Marseille07 »

birdog wrote: Thu Mar 18, 2021 8:44 am Wow! This thing tells me I'm going to be rich! Rich, I tell you!!! Muuuuu uuuuuu haaaaa!!!!

This provided the most optimistic projections I've seen.
Really? When I casually ran w/ default inputs, the 4% SWR scenario running 75/25 would fail multiple years during the 60s.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by birdog »

Marseille07 wrote: Thu Mar 18, 2021 10:21 am
birdog wrote: Thu Mar 18, 2021 8:44 am Wow! This thing tells me I'm going to be rich! Rich, I tell you!!! Muuuuu uuuuuu haaaaa!!!!

This provided the most optimistic projections I've seen.
Really? When I casually ran w/ default inputs, the 4% SWR scenario running 75/25 would fail multiple years during the 60s.
For me, Personal Capital projects 96% success rate with final median value (at age 90) of X. The same inputs in Cfiresim get me 100% success rate and final median value of 4.4X.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

nigel_ht wrote: Thu Mar 18, 2021 9:10 am Lauren,

Nice job. I've never actually used it before but the new iteration is nice and clean. I am curious that 60/40, 0 fees and 4% SWR results in 5 failures for a retirement starting 2021 and ending 2050. They are all in the expected 1964-1969 range but I had thought there were only 2 years where it failed (1965 and 1966). Oddly, it reports 5 failures but the Single Portfolio Dips shows 6 instances of $0 results. 1964 was in cycle 29 so maybe it doesn't count?

https://www.cfiresim.com/d0846f44-027a- ... 7e16273e8e
Off the top of my head... I'm not sure why it's 5 vs 6... but I will investigate this weekend. Consider it "added to the list" haha.

A rough approximation of Golden Butterfly 40/40/20 results in 5 reported failures but 9 zero dollar results. Looks like the same pattern...failures in the last year don't count which I guess is okay but I'm assuming that in many of these you didn't get the full $40K for that year.

https://www.cfiresim.com/d5e1351d-49c7- ... f29629cf97
After looking at that one, I feel like you're onto something, and to me it looks semi-obvious that it might not be counting it as a "failure" if you reach $0 in the last year. While I think that maybe there is a philosophical reason to NOT consider it a failure in the final year (ha, you're dead?), from a technical standpoint, it seems like an "off-by-one" calculation miss. I'll figure it out! Thanks for pointing it out! It's sometimes really hard to test your own software, because of your bias from being "in" it all of the time.

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by Marseille07 »

birdog wrote: Thu Mar 18, 2021 10:48 am
Marseille07 wrote: Thu Mar 18, 2021 10:21 am
birdog wrote: Thu Mar 18, 2021 8:44 am Wow! This thing tells me I'm going to be rich! Rich, I tell you!!! Muuuuu uuuuuu haaaaa!!!!

This provided the most optimistic projections I've seen.
Really? When I casually ran w/ default inputs, the 4% SWR scenario running 75/25 would fail multiple years during the 60s.
For me, Personal Capital projects 96% success rate with final median value (at age 90) of X. The same inputs in Cfiresim get me 100% success rate and final median value of 4.4X.
That's strange. I quickly compared with firecalc and the results looked quite comparable...
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by 1210sda »

Lauren,

For a given portfolio level and desired success percent, is there a way to determine the maximum annual withdrawal ?
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

lauren_knows wrote: Thu Mar 18, 2021 10:54 am
nigel_ht wrote: Thu Mar 18, 2021 9:10 am Lauren,

Nice job. I've never actually used it before but the new iteration is nice and clean. I am curious that 60/40, 0 fees and 4% SWR results in 5 failures for a retirement starting 2021 and ending 2050. They are all in the expected 1964-1969 range but I had thought there were only 2 years where it failed (1965 and 1966). Oddly, it reports 5 failures but the Single Portfolio Dips shows 6 instances of $0 results. 1964 was in cycle 29 so maybe it doesn't count?

https://www.cfiresim.com/d0846f44-027a- ... 7e16273e8e
Off the top of my head... I'm not sure why it's 5 vs 6... but I will investigate this weekend. Consider it "added to the list" haha.

A rough approximation of Golden Butterfly 40/40/20 results in 5 reported failures but 9 zero dollar results. Looks like the same pattern...failures in the last year don't count which I guess is okay but I'm assuming that in many of these you didn't get the full $40K for that year.

https://www.cfiresim.com/d5e1351d-49c7- ... f29629cf97
After looking at that one, I feel like you're onto something, and to me it looks semi-obvious that it might not be counting it as a "failure" if you reach $0 in the last year. While I think that maybe there is a philosophical reason to NOT consider it a failure in the final year (ha, you're dead?), from a technical standpoint, it seems like an "off-by-one" calculation miss. I'll figure it out! Thanks for pointing it out! It's sometimes really hard to test your own software, because of your bias from being "in" it all of the time.

-Lauren
Already found and fixed the bug. It was definitely missing the very final year as a "failure". Thanks nigel_ht!

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

1210sda wrote: Thu Mar 18, 2021 11:17 am Lauren,

For a given portfolio level and desired success percent, is there a way to determine the maximum annual withdrawal ?
Yup. Set up your portfolio, and then click the "Open Investigation Panel" button at the top right of the Basics section. It will pop open a new section, where you can toggle an investigation of Maximum Spending, given a success threshold. It shows the result on the Output page under the graph.

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by nigel_ht »

1210sda wrote: Thu Mar 18, 2021 11:17 am Lauren,

For a given portfolio level and desired success percent, is there a way to determine the maximum annual withdrawal ?
there is a switch you can set under "Investigation Options". For 60/40 it tells me that the $41650 is the max initial spend for success at 95% success rate. For 100% success rate it is $36230...hmmm...
Last edited by nigel_ht on Thu Mar 18, 2021 11:22 am, edited 1 time in total.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

birdog wrote: Thu Mar 18, 2021 10:48 am
Marseille07 wrote: Thu Mar 18, 2021 10:21 am
birdog wrote: Thu Mar 18, 2021 8:44 am Wow! This thing tells me I'm going to be rich! Rich, I tell you!!! Muuuuu uuuuuu haaaaa!!!!

This provided the most optimistic projections I've seen.
Really? When I casually ran w/ default inputs, the 4% SWR scenario running 75/25 would fail multiple years during the 60s.
For me, Personal Capital projects 96% success rate with final median value (at age 90) of X. The same inputs in Cfiresim get me 100% success rate and final median value of 4.4X.
Personal Capital is doing a monte carlo analysis I think, with a whole set of assumptions that I have no idea about. If you want to share the cFIREsim link on your output page, I can field any questions *shrug*
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by 1210sda »

lauren_knows wrote: Thu Mar 18, 2021 11:20 am
1210sda wrote: Thu Mar 18, 2021 11:17 am Lauren,

For a given portfolio level and desired success percent, is there a way to determine the maximum annual withdrawal ?
Yup. Set up your portfolio, and then click the "Open Investigation Panel" button at the top right of the Basics section. It will pop open a new section, where you can toggle an investigation of Maximum Spending, given a success threshold. It shows the result on the Output page under the graph.

-Lauren
Thank you. At first I didn't notice the switch that I had to turn on.

Is there a way to print and/or save this?

P.S. Sorry to come off as such a dummy, but the first time I tried to click on the "Open Investigations Panel", I double clicked and it opened and then closed the panel. Just FYI
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

1210sda wrote: Thu Mar 18, 2021 11:33 am
lauren_knows wrote: Thu Mar 18, 2021 11:20 am
1210sda wrote: Thu Mar 18, 2021 11:17 am Lauren,

For a given portfolio level and desired success percent, is there a way to determine the maximum annual withdrawal ?
Yup. Set up your portfolio, and then click the "Open Investigation Panel" button at the top right of the Basics section. It will pop open a new section, where you can toggle an investigation of Maximum Spending, given a success threshold. It shows the result on the Output page under the graph.

-Lauren
Thank you. At first I didn't notice the switch that I had to turn on.

Is there a way to print and/or save this?

P.S. Sorry to come off as such a dummy, but the first time I tried to click on the "Open Investigations Panel", I double clicked and it opened and then closed the panel. Just FYI
Honestly, my tutorials and documentation are severely lacking, so no apologies needed. I'm in the process of massively updating them.

To "save" your simulation, you can refer to the link on the Output page right above the graph. That will return you to the same inputs later if you want. Also next to that graph is a CSV download that has info on literally every simulation cycle (but again, the fields in that CSV aren't super well documented yet). Other than that, you can certainly print the Output page :)

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by nigel_ht »

lauren_knows wrote: Thu Mar 18, 2021 11:18 am
lauren_knows wrote: Thu Mar 18, 2021 10:54 am
nigel_ht wrote: Thu Mar 18, 2021 9:10 am Lauren,

Nice job. I've never actually used it before but the new iteration is nice and clean. I am curious that 60/40, 0 fees and 4% SWR results in 5 failures for a retirement starting 2021 and ending 2050. They are all in the expected 1964-1969 range but I had thought there were only 2 years where it failed (1965 and 1966). Oddly, it reports 5 failures but the Single Portfolio Dips shows 6 instances of $0 results. 1964 was in cycle 29 so maybe it doesn't count?

https://www.cfiresim.com/d0846f44-027a- ... 7e16273e8e
Off the top of my head... I'm not sure why it's 5 vs 6... but I will investigate this weekend. Consider it "added to the list" haha.

A rough approximation of Golden Butterfly 40/40/20 results in 5 reported failures but 9 zero dollar results. Looks like the same pattern...failures in the last year don't count which I guess is okay but I'm assuming that in many of these you didn't get the full $40K for that year.

https://www.cfiresim.com/d5e1351d-49c7- ... f29629cf97
After looking at that one, I feel like you're onto something, and to me it looks semi-obvious that it might not be counting it as a "failure" if you reach $0 in the last year. While I think that maybe there is a philosophical reason to NOT consider it a failure in the final year (ha, you're dead?), from a technical standpoint, it seems like an "off-by-one" calculation miss. I'll figure it out! Thanks for pointing it out! It's sometimes really hard to test your own software, because of your bias from being "in" it all of the time.

-Lauren
Already found and fixed the bug. It was definitely missing the very final year as a "failure". Thanks nigel_ht!

-Lauren
You're welcome and again, nicely done. Yep, it's the classic < vs <= off by one bug. Out of curiosity what did you write this in?

Oh, was it intended for the UI to be 0 based for the cycle count? It makes sense to me (programmer) but failure on year 2 is cycle 1...

Aaaand...how hard would it be to add datasets? It would be amusing to see the Nikkei in there. Just because. Actually that feature would be more useful for adding more granularity beyond "equities" and "bonds"...

Firecalc really looks like a product of the dot bomb era...all it needs is a flaming rotating logo. Okay, I'm being snarky...but cFireSim is nice.

It takes more than a little jQuery and bootstrap to make a site not suck and this works pretty well. It'll be interesting to see how you deal with adding "expert" features we're going to start clamoring for. :)

Hmmm...keep adding to the hidden area for Investigation Options or toggle between an expert and basic mode?
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by billthecat »

rgs92 wrote: Fri Mar 12, 2021 8:31 am I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
What is the relationship between that and the other cfiresim at https://alistair-marshall.github.io/cFIREsim-open/? Maybe Lauren knows?
We cannot direct the winds but we can adjust our sails.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by Marseille07 »

billthecat wrote: Thu Mar 18, 2021 12:04 pm
rgs92 wrote: Fri Mar 12, 2021 8:31 am I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
What is the relationship between that and the other cfiresim at https://alistair-marshall.github.io/cFIREsim-open/? Maybe Lauren knows?
https://github.com/alistair-marshall/cFIREsim-open

Basically that person forked the old cFIREsim and added features. I was using his before Lauren revamped the original.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

nigel_ht wrote: Thu Mar 18, 2021 11:59 am
You're welcome and again, nicely done. Yep, it's the classic < vs <= off by one bug. Out of curiosity what did you write this in?
It's a Python/Django application. It's what I'm comfortable with (my day job).
Oh, was it intended for the UI to be 0 based for the cycle count? It makes sense to me (programmer) but failure on year 2 is cycle 1...
Yeah, I honestly didn't change it from the 0-index Python list. I didn't want to have to convert back and forth, because there is a lot of logic working off of the Cycle index. *shrug*
Aaaand...how hard would it be to add datasets? It would be amusing to see the Nikkei in there. Just because. Actually that feature would be more useful for adding more granularity beyond "equities" and "bonds"...
This is something I've wanted to do for a LONG time, but I can't systematically figure out how to do it, because I currently have a nice tidy dataset for Stocks/Bonds/Gold all the way back to 1871... and other datasets like the Nikkei, or the FTSE only go back 80 years, so I don't know how to reconcile datasets with different length. (or at least I haven't had a good discussion with anyone about it).
Firecalc really looks like a product of the dot bomb era...all it needs is a flaming rotating logo. Okay, I'm being snarky...but cFireSim is nice.
LOL, ain't that the truth. I mean, it's because the person who wrote it retired to a sailboat 10+ years ago, and sold it to a company that runs a discussion forum. They're doing the bare-minimum to keep it alive. I literally reverse-engineered Firecalc 9 years ago to develop cFIREsim, SPECIFICALLY because people were clamoring for quality-of-life features and I thought it'd be a fun project (because I'm super interested in FIRE).
It takes more than a little jQuery and bootstrap to make a site not suck and this works pretty well. It'll be interesting to see how you deal with adding "expert" features we're going to start clamoring for. :)

Hmmm...keep adding to the hidden area for Investigation Options or toggle between an expert and basic mode?
Yeah, it certainly does take more than that. It doesn't help that I'm primarily a back-end developer haha. In my limited free time, I'm trying to go through some ReactJS and VueJS courses to get a better handle on front-end tech. But, the site is already a monstrosity of a giant web form... I'm happily surprised that people think that it's semi-easy to use still :)

-Lauren
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by lauren_knows »

Marseille07 wrote: Thu Mar 18, 2021 12:07 pm
billthecat wrote: Thu Mar 18, 2021 12:04 pm
rgs92 wrote: Fri Mar 12, 2021 8:31 am I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
What is the relationship between that and the other cfiresim at https://alistair-marshall.github.io/cFIREsim-open/? Maybe Lauren knows?
https://github.com/alistair-marshall/cFIREsim-open

Basically that person forked the old cFIREsim and added features. I was using his before Lauren revamped the original.
Exactly this. There was a period of time after I released cFIREsim where I had 2 children, did a career change, and had other life transitions that just took up a ton of my time. That person forked my open-source code, and added some minimal features. The current version I have is closed-source, and I'm in a much better place in my life to maintain it... and have been entering the Personal Finance and FIRE social media circles... because it's fun :)

-Lauren
39 - Married - 2 kids - Aiming for FI/ER in early 40s - Creator of cFIREsim
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by nigel_ht »

lauren_knows wrote: Thu Mar 18, 2021 12:13 pm
Marseille07 wrote: Thu Mar 18, 2021 12:07 pm
billthecat wrote: Thu Mar 18, 2021 12:04 pm
rgs92 wrote: Fri Mar 12, 2021 8:31 am I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
What is the relationship between that and the other cfiresim at https://alistair-marshall.github.io/cFIREsim-open/? Maybe Lauren knows?
https://github.com/alistair-marshall/cFIREsim-open

Basically that person forked the old cFIREsim and added features. I was using his before Lauren revamped the original.
Exactly this. There was a period of time after I released cFIREsim where I had 2 children, did a career change, and had other life transitions that just took up a ton of my time. That person forked my open-source code, and added some minimal features. The current version I have is closed-source, and I'm in a much better place in my life to maintain it... and have been entering the Personal Finance and FIRE social media circles... because it's fun :)

-Lauren
Yah, that's pretty par for the course for Open Source. And given one path to FIRE is a decent side hustle I would keep this closed source even if I am normally an open source advocate. Looking at GitHub I think you won the open source lotto in that it looks like you got a decent number of commits from another contributor. Most of the time you get some random pull request that would take you longer to understand than write from scratch...
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by vandering »

Congratulations LAUREN on your achievement. This is by far the best retirement calculator I've used and the only one I bookmarked. Thank-you. If you decide to monetize this program in some way, I'm sure many in your audience would be receptive despite our "making pennies scream" mindset.
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Re: Cfiresim has been revised and is super easy to use. (It's based on Firecalc)

Post by billthecat »

Marseille07 wrote: Thu Mar 18, 2021 12:07 pm
billthecat wrote: Thu Mar 18, 2021 12:04 pm
rgs92 wrote: Fri Mar 12, 2021 8:31 am I just wanted to alert people here that Cfiresim's user-interface has been completely redone so it is now extremely clear and easy to use. Anyone can use it easily. So if you are new to this or intimidated by financial software or even personal investing in general, I encourage you to give it a try.
It is a very simple and clear way to see where you stand in achieving your financial goals in a DIY approach. And it's free.
So if you are a noobie or feel in need of help, this is a great place to start.

As someone who had a career designing customer-facing software and user interfaces, I am mightily impressed with the clear and smart design revision of Cfiresim.

https://www.cfiresim.com/
What is the relationship between that and the other cfiresim at https://alistair-marshall.github.io/cFIREsim-open/? Maybe Lauren knows?
https://github.com/alistair-marshall/cFIREsim-open

Basically that person forked the old cFIREsim and added features. I was using his before Lauren revamped the original.
Thanks, i expect I'll do the same.
We cannot direct the winds but we can adjust our sails.
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