Asset allocation

investopedia says: An investment strategy that aims to balance risk and reward by apportioning a portfolio's assets according to an individual's goals, risk tolerance and investment horizon.

The three main asset classes - equities, fixed-income, and cash and equivalents - have different levels of risk and return, so each will behave differently over time.

There is no simple formula that can find the right asset allocation for every individual. However, the consensus among most financial professionals is that asset allocation is one of the most important decisions that investors make. In other words, your selection of individual securities is secondary to the way you allocate your investment in stocks, bonds, and cash and equivalents, which will be the principal determinants of your investment results.

Rules of thumb
Although your exact asset allocation should depend on your goals for the money, some rules of thumb exist to guide your decision.

The most important asset allocation decision is the split between risky and non-risky assets. This is most often referred to as the stock/bond split. Graham's timeless advice was to never hold less than 25% of your portfolio in bonds (or more than 75%). Bogle recommends "your age in bonds"; for instance, if you are 45, 45% of your portfolio should be in high-quality bonds. Recently, less conservative rules have emerged such as (age - 10) or even (age - 20) in bonds. Investors choosing to use these guidelines should understand why they feel they have the need, ability, and willingness to take on the greater risk inherent in having a higher proportion of equities. All age-based guidelines are predicated on the assumption that an individual's circumstances mirror the general population's. Individuals with different retirement ages (earlier or later), asset levels (those who have saved enough to fund their retirement fully with TIPS, or needs for the money (e.g. college savings) would be well-advised to consider what circumstances make their situation different and adjust their AA accordingly.

Asset allocation funds
Asset-allocation mutual funds, also known as life-cycle, or target-date, funds, are an attempt to provide investors with portfolio structures that address an investor's age, risk appetite and investment objectives with an appropriate apportionment of asset classes. However, critics of this approach point out that arriving at a standardized solution for allocating portfolio assets is problematic because individual investors require individual solutions.


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