The 60/40 Portfolio as a Benchmark and Its Limits

Summary

The document explains the traditional 60/40 allocation: 60% in equities and 40% in bonds, periodically rebalanced to restore those weights. It presents the portfolio as a simple, low-cost benchmark that can use domestic or global assets. Its rationale is diversification from historically imperfect stock-bond correlation, with bonds intended to temper volatility and drawdowns. Infrequent rebalancing may also reduce trading and realized gains compared with more active approaches.

For a US implementation over the stated 2003–2019 period, the document reports a 7% compound annual growth rate, 10% annualized volatility, and a 0.73 Sharpe ratio. It also cites a 35% maximum drawdown during the global financial crisis. The author cautions that results benefited from strong US equities, quantitative easing, and low inflation; expensive stocks and low bond yields could weaken future real returns. Stock-bond correlation may also rise, undermining the diversification premise. The historical figures are period-specific and do not establish future performance.

Key ideas

• A 60/40 portfolio allocates capital between equities and bonds and periodically rebalances to maintain target weights.
• The allocation aims to combine equity returns with lower volatility through diversification across asset classes.
• The document reports strong historical performance for a US portfolio over 2003–2019, including a sizable crisis drawdown.
• Past results were supported by market conditions that may not persist, including low inflation and declining bond yields.
• Higher stock-bond correlation could reduce the portfolio’s diversification benefit.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.