What maximum drawdown measures
Maximum drawdown is the largest percentage decline from a previous high to a later low. If a portfolio grows to $500,000 and then falls to $350,000 before recovering, that decline is a 30% drawdown. The measure focuses on the investor's lived experience: how much value disappeared from the high point before the portfolio recovered.
Drawdown is different from volatility. Volatility measures how much returns vary. Drawdown measures the depth of an actual decline along the path. A portfolio can have moderate volatility but still experience a painful drawdown if losses cluster together.
Why final values are not enough
Many long-term projections emphasize the ending balance. That number is important, but it does not show whether the path required the investor to sit through a 25%, 40%, or 60% decline. In real life, investors often abandon plans during drawdowns, not during smooth averages.
Portfolio Modeler shows a drawdown distribution so the user can compare potential stress between portfolios. A higher-return portfolio may produce a larger ending value, but if the simulated drawdowns are too severe for the investor to tolerate, the plan may not be realistic.
Drawdowns and withdrawals
Drawdowns become especially important when withdrawals are included. Selling assets during a decline can lock in losses and reduce the capital available for recovery. This is part of sequence-of-return risk, and it is one reason retirement projections should not rely only on average annual return.
A percentage withdrawal can reduce spending automatically when the portfolio falls. A fixed dollar withdrawal keeps spending more stable, but it can put more pressure on the portfolio during bad markets. Testing both settings can help visitors understand the tradeoff.
How to use the drawdown chart
The drawdown chart should be read as an estimated range, not as a worst-case guarantee. Future markets can produce declines outside the historical sample. Still, the chart is useful for comparing one portfolio against another under the same modeling assumptions.
- Compare median drawdown before focusing on upside outcomes.
- Check whether a lower-risk allocation meaningfully reduces the downside range.
- Stress test withdrawal settings because cash flows can deepen the effect of poor early returns.
- Remember that a tolerable portfolio is often more useful than a theoretically optimal one.