Balanced vs all equity

60/40 vs 100% S&P 500

Compare a balanced 60/40 portfolio against an all-equity S&P 500 portfolio across the same pre-tax historical window.

Modeled result

From 2005 to 2025, SPY finished ahead of SPY 60% / AGG 40% before tax.

Change dates in Portfolio Backtest

Historical model

Growth of $10,000

2005-01-03 to 2025-12-31

Chart window

All history

Chart window

Pre-tax growth for Classic 60/40 and SPY from 2005-01-03 to 2025-12-31. Classic 60/40 ends at $49,284; SPY ends at $83,565.
HoldingEnding valueCAGRMax drawdown

SPY 60% / AGG 40%

Classic 60/40

$49,2847.89%-35.56%

SPY

S&P 500 only

$83,56510.64%-55.19%
  • SPY 60% / AGG 40%

    Classic 60/40

    CAGR
    7.89%
    Max drawdown
    -35.56%
  • SPY

    S&P 500 only

    CAGR
    10.64%
    Max drawdown
    -55.19%

Pre-tax results only. Bond-interest taxation and taxable gains from rebalancing are not included in this comparison.

Detailed metrics

HoldingPre-tax valuePre-tax CAGRMax drawdown

Classic 60/40

SPY 60% / AGG 40%

$49,2847.89%-35.56%

S&P 500 only

SPY

$83,56510.64%-55.19%

Assumptions

$10,000 lump sum; distributions reinvested; monthly rebalancing; 2005-01-03 to 2025-12-31.

FAQ

Does adding bonds always reduce return?

Not necessarily. Bonds lower volatility and drawdowns in most windows, and the return difference depends on the period. In some windows the balanced mix trails all-equity; in others its smaller drawdowns change the outcome. The backtest shows the tradeoff for your inputs.

How do taxes affect a 60/40 portfolio?

This page does not estimate them. In a taxable account the bond sleeve can generate ordinary-income interest, while rebalancing can realize gains. Model those effects in a separate tax-aware run.

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