Diversification is the only free lunch in investing.
Educational content: This lesson explains general portfolio allocation concepts and common rules of thumb. These are illustrative examples, not recommendations for your personal situation. Your ideal allocation depends on your specific goals, timeline, risk tolerance, and financial circumstances. Consider consulting a qualified financial advisor for personalized guidance.
What Is Portfolio Allocation?
Portfolio allocation is how you divide your investments among different asset types. Think of it as deciding what percentage goes where.
Research shows that asset allocation determines about 90% of your portfolio's long-term performance. The specific stocks you pick matter far less than whether you're 80% stocks or 50% stocks.
Main Asset Classes
- Stocks (Equities): Ownership in companies. High growth potential, high volatility.
- Bonds (Fixed Income): Loans to governments/companies. Lower returns, more stable.
- International: Stocks/bonds from outside your home country. Adds diversification.
What determines most of your portfolio's long-term performance?
Stocks vs. Bonds: The Core Decision
The most important allocation decision is how much goes in stocks versus bonds.
Stocks
- Average return: ~10%/year historically
- Can drop 30-50% in bear markets
- Best for long-term growth (10+ years)
- More volatile but higher rewards
Bonds
- Average return: ~4-5%/year historically
- Usually don't drop as much in crashes
- Provide stability and income
- Less growth but smoother ride
2008 Financial Crisis Example
100% Stocks
-37%
60% Stocks / 40% Bonds
-22%
100% Bonds
+5%
Bonds cushioned the blow significantly during the worst crash since the Great Depression.
Age-Based Allocation
The classic rule: “110 minus your age” equals your stock percentage.
| Age | Stocks | Bonds | Risk Level |
|---|---|---|---|
| 25 | 85% | 15% | Aggressive |
| 35 | 75% | 25% | Growth |
| 45 | 65% | 35% | Balanced |
| 55 | 55% | 45% | Moderate |
| 65 | 45% | 55% | Conservative |
Why Age Matters
Young investors have decades to recover from crashes. A 30-year-old can wait out a 50% drop. A 65-year-old about to retire can't. More bonds as you age = protecting what you've built.
Using the '110 minus age' rule, what stock allocation should a 40-year-old have?
Sample Portfolios
Young Aggressive (Age 25-35)
- 60% US Total Market (VTI)
- 30% International (VXUS)
- 10% Bonds (BND)
Maximum growth potential. Can handle volatility.
Mid-Career Balanced (Age 40-50)
- 45% US Total Market (VTI)
- 20% International (VXUS)
- 35% Bonds (BND)
Balance of growth and stability.
Near Retirement (Age 55-65)
- 30% US Total Market (VTI)
- 15% International (VXUS)
- 55% Bonds (BND)
Protecting accumulated wealth.
Ultra-Simple (Any Age)
- 100% Target Date Fund
- (e.g., Vanguard 2055)
One fund that auto-adjusts as you age. Set and forget.
Rebalancing: Staying on Track
Over time, your allocation drifts. If stocks do well, you might end up 90% stocks when you wanted 80%. Rebalancing brings you back to your target.
How to Rebalance
- 1. Check allocations - What's your current mix?
- 2. Compare to targets - How far off are you?
- 3. Sell high, buy low - Sell what's over-allocated, buy what's under
- 4. Or redirect new money - Put new contributions into under-allocated assets
Once a year is enough. Many people rebalance on their birthday or January 1st.
The Bottom Line
Allocation decisions depend on individual circumstances, goals, and risk tolerance. Some investors prefer simple approaches; others prefer more complex ones. There's no universal “right” answer. This is educational information — consult a financial professional for personalized advice.
Next, we'll cover one of the hardest topics: knowing when to sell.