OK simple tweak applies 2% compound COLA to starting monthly benefit provided on PEBES report, for 0 years if start at 62, 5 years if start at 67 (66 2/3), 8 years if start at 70.
As predicted, this moves the crossover to age 81 for both waiting to age 66 2/3 or 70. I need to reconsider my plan.
I discovered a free Kotlikoff site with a stripped down planner which is helpful.
http://basic.esplanner.com/
I recognize risks, there are many. Long lifespan equals wait. Short lifespan is a risk too, the risk being that money is left on the table. For example, my mother planned to retire at 65 and take benefits. About age 64 while still working she was unexpectedly diagnosed with stage 3 endometrial cancer. We processed emergency retirement turning on pensions and SS. She had received only about 1.5 years of benefits when she passed at age 66. Similar situation, the money wasn't needed to retire it was to pile up in investment accounts. She did not enjoy her work much and would have benefited from early retirement at age 62 through more years in retirement, and arguably a higher net worth at death which could be left to charity or heirs.
Other risks are the rules can be changed although I think that is unlikely to affect people already near or post FRA, there will be some grandfathering for people who have planned by current rules and congress won't suddenly change the rules to pull the rug out from under them. Taxation of benefits can change, there are many things.
It seems though that if someone contemplates purchase of longevity insurance or a life annuity to prevent 'running out of money', waiting is a very efficient way to 'purchase' that annuity.
Here's the modified spreadsheet, and it still ignores taxes for simplicity.
Social Security Early Benefits Worksheet
3% Estimated return can earn on invested capital
2% COLA estimate, applies also to base benefit amounts if taken after age 62
SS Monthly per PEBES $1,263 $1,752 $2,219
# Years COLA Before Start $- $5 $8
Adj for COLA $1,263 $1,934 $2,600
Year Age Yearly Benefit Acct Balance Yearly Benefit Acct Balance Yearly Benefit Acct Balance
2020 62 $15,156 $15,156
2021 63 $15,459 $31,070
2022 64 $15,768 $47,770
2023 65 $16,084 $65,287
2024 66 $16,405 $83,651
2025 67 $16,733 $102,894 $23,212 $23,212
2026 68 $17,068 $123,049 $23,676 $47,585
2027 69 $17,409 $144,150 $24,150 $73,163
2028 70 $17,758 $166,232 $24,633 $99,990 $31,199 $31,199
2029 71 $18,113 $189,332 $25,126 $128,116 $31,823 $63,958
2030 72 $18,475 $213,487 $25,628 $157,587 $32,459 $98,336
2031 73 $18,845 $238,736 $26,141 $188,456 $33,109 $134,395
2032 74 $19,221 $265,119 $26,664 $220,773 $33,771 $172,197
2033 75 $19,606 $292,679 $27,197 $254,593 $34,446 $211,809
2034 76 $19,998 $321,457 $27,741 $289,971 $35,135 $253,299
2035 77 $20,398 $351,499 $28,296 $326,966 $35,838 $296,735
2036 78 $20,806 $382,850 $28,861 $365,636 $36,555 $342,192
2037 79 $21,222 $415,558 $29,439 $406,044 $37,286 $389,743
2038 80 $21,647 $449,671 $30,027 $448,253 $38,031 $439,467
2039 81 $22,079 $485,240 $30,628 $492,329 $38,792 $491,443
2040 82 $22,521 $522,319 $31,241 $538,339 $39,568 $545,754
2041 83 $22,971 $560,960 $31,865 $586,354 $40,359 $602,486
2042 84 $23,431 $601,219 $32,503 $636,448 $41,166 $661,727
2043 85 $23,899 $643,155 $33,153 $688,694 $41,990 $723,568
2044 86 $24,377 $686,827 $33,816 $743,171 $42,829 $788,105
2045 87 $24,865 $732,297 $34,492 $799,958 $43,686 $855,434
2046 88 $25,362 $779,628 $35,182 $859,138 $44,560 $925,657
2047 89 $25,870 $828,887 $35,886 $920,798 $45,451 $998,877
2048 90 $26,387 $880,140 $36,603 $985,025 $46,360 $1,075,204
2049 91 $26,915 $933,459 $37,335 $1,051,912 $47,287 $1,154,747
2050 92 $27,453 $988,916 $38,082 $1,121,551 $48,233 $1,237,622
2051 93 $28,002 $1,046,586 $38,844 $1,194,041 $49,198 $1,323,949
2052 94 $28,562 $1,106,545 $39,621 $1,269,483 $50,182 $1,413,849
2053 95 $29,133 $1,168,875 $40,413 $1,347,980 $51,185 $1,507,449
2054 96 $29,716 $1,233,657 $41,221 $1,429,641 $52,209 $1,604,882
2055 97 $30,310 $1,300,977 $42,046 $1,514,576 $53,253 $1,706,281
2056 98 $30,917 $1,370,923 $42,887 $1,602,900 $54,318 $1,811,788
2057 99 $31,535 $1,443,586 $43,744 $1,694,731 $55,404 $1,921,546
2058 100 $32,166 $1,519,059 $44,619 $1,790,192 $56,513 $2,035,705