Asset Allocation

What Is Asset Allocation?

By now you know what to invest in — low-cost index funds. The next question is how to divide your money among different types of investments. That decision is called asset allocation, and research consistently shows it matters more than picking specific funds or timing when you buy.

Think of it like a recipe. The individual ingredients (which specific index fund you pick) matter less than the proportions (how much stock vs. bond). A portfolio that's 90% stocks and 10% bonds will behave very differently from one that's 50% stocks and 50% bonds — even if both use the same index funds. The mix is the main event.

Stocks vs. Bonds: The Core Trade-Off

Stocks have historically returned about 10% per year on average (roughly 7% after inflation). But they're volatile — the stock market drops 10%+ about once a year, and 20%+ every 3–5 years. Over long periods (20+ years), stocks have always recovered and grown, but the short-term swings can be stomach-churning.

Bonds have historically returned about 5% per year (roughly 2% after inflation). They're much steadier — bonds rarely drop as sharply as stocks, and they often hold value or rise when stocks are falling. The trade-off is significantly lower long-term growth.

More stocks = higher expected return, more volatility. More bonds = lower expected return, smoother ride. Asset allocation is where you decide how much volatility you're willing to accept in exchange for growth.

Age-Based Guidelines

A common starting point is the "110 minus your age" rule: subtract your age from 110 to get the percentage you put in stocks. The rest goes in bonds. At age 25, that's 85% stocks / 15% bonds. At age 50, it's 60% stocks / 40% bonds. At age 65, it's 45% stocks / 55% bonds.

The logic: when you're young, you have decades for your portfolio to recover from drops, so you can hold more stocks and capture their higher long-term growth. As you get closer to needing the money, you gradually shift toward bonds to reduce the chance of a big drop right when you need to withdraw.

This is a starting point, not gospel. Your ideal allocation depends on factors beyond age: when you plan to retire, how stable your income is, whether you have other sources of retirement income, and how you react emotionally to market drops. Someone who panics and sells every time stocks drop 15% may be better off with more bonds, even if they're young — a conservative portfolio you stick with beats an aggressive portfolio you bail on.

Target-Date Funds: Autopilot Allocation

If choosing your own allocation sounds overwhelming, target-date funds (also called lifecycle funds) do it for you. You pick the fund closest to the year you plan to retire — a "Target 2055" fund if you're retiring around 2055 — and the fund automatically adjusts the stock/bond mix over time, getting more conservative as the target date approaches.

A Target 2055 fund today might be 90% stocks / 10% bonds. By 2040 it might be 70/30. By 2055 it might be 50/50. This gradual shift is called a "glide path."

Target-date funds are a perfectly reasonable choice, especially in a 401(k) where your options are limited. The main trade-off: they charge slightly higher fees than building your own two- or three-fund portfolio (typically 0.10–0.15% vs. 0.03–0.05%), and you can't customize the glide path. But "pretty good and automatic" often beats "theoretically optimal but never implemented."

Risk Tolerance vs. Risk Capacity

These sound similar but they're different, and the gap between them causes real problems.

Risk capacity is what your financial situation can handle. A 25-year-old with a stable job and 35 years until retirement has high risk capacity — even a 40% portfolio drop doesn't matter because there's plenty of time to recover. A 60-year-old planning to retire in 2 years has low risk capacity — a big drop right before retirement could force them to work longer or withdraw less.

Risk tolerance is what your emotions can handle. Some people can watch their portfolio drop 30% and shrug it off. Others lose sleep when it drops 10%. This isn't a character flaw — it's just how different people are wired.

Rebalancing: Keeping Your Mix on Target

Over time, stocks tend to grow faster than bonds, so an unattended portfolio slowly drifts toward higher stock percentages — and higher risk — than you intended. Rebalancing prevents that drift from accumulating.

How often should you rebalance? Most advisors suggest checking once or twice a year, or whenever an asset class drifts more than 5 percentage points from your target. Many 401(k) plans offer automatic rebalancing. Target-date funds handle it internally.

Rebalancing feels counterintuitive — you're selling whatever is "winning" and buying whatever is "losing." But that's exactly the point. You're maintaining the risk level you chose and systematically buying low and selling high.

This Isn't Stock Picking

It's worth repeating: asset allocation is about the mix of broad asset classes, not about picking individual companies or sectors. Deciding to hold 80% stocks doesn't mean picking which 10 stocks to buy. It means owning a broad stock index fund (which holds thousands of companies) at 80% of your portfolio. The "what to buy" question was already answered in the previous article on index fund investing. Asset allocation is the "how much of each" question.

A Brief Note on Tax-Efficient Placement

Once you've decided on your stock/bond split, there's a secondary question: which account should hold which assets? This is called asset location (not to be confused with asset allocation).

The basic idea: bonds generate regular interest income that gets taxed at your ordinary income tax rate. If those bonds sit in a tax-deferred account (like a 401(k) or traditional Individual Retirement Account), you don't pay taxes on that interest until you withdraw decades later. Stocks, on the other hand, benefit from lower long-term capital gains tax rates, so they're relatively more tax-friendly in a regular taxable brokerage account.

This matters more as your portfolio grows. Early on, most people only have a 401(k) or Roth IRA (Individual Retirement Account), so everything goes in one place and that's fine. As you accumulate money in both retirement and taxable accounts, placing bonds in tax-deferred accounts and stocks in taxable accounts can improve your after-tax returns by a small but meaningful amount.

We'll cover tax optimization in more detail in Level 4. For now, just know the principle: tax-inefficient assets (bonds) do best in tax-sheltered accounts; tax-efficient assets (stocks) do fine anywhere.