What Is Maximum Drawdown (MDD)?
No matter how high your return is, if you had to endure a -50% along the way, could you have stayed invested? MDD is the metric that answers that question.
What Is MDD?
MDD (Maximum Drawdown) is a metric showing the largest peak-to-trough decline during an investment period. For example, if a portfolio started at about $7,400, peaked at about $11,100, and then fell to about $5,600, the MDD is -50% from the peak.
It shows not just "how much you lost" but "how much you had to endure in the worst case." That is exactly why it must always be checked alongside your return.
Historical Case: The MDD of the S&P 500
2008 Global Financial Crisis: The S&P 500 fell -56.8% from its peak (October 2007) to its trough (March 2009). It took 52 months (about 4.3 years) to recover to the original level.
2000 Dot-com bubble burst: The S&P 500 fell -49.1%, taking 84 months (about 7 years) to recover. The Nasdaq was far worse at -78.4%, and it took a full 15 years (until 2015) to recover its 2000 peak.
2020 COVID-19 pandemic: The S&P 500 fell -33.9%, entering a bear market in just 33 days. Yet it staged one of the fastest recoveries in history, regaining its original level in just 5 months.
The larger the MDD, the more return is needed to recover. After a -50% decline, a +100% gain is required just to break even.
MDD and the Holding Period
In long-term investing, MDD is unavoidable. What matters is how long you can endure it.
The longer the investment period, the higher the chance of experiencing a large MDD. Between a 1-year and a 20-year investment, the 20-year one is more likely to experience a larger MDD. But long-term investing also allows enough time to recover.
The historical MDD of a diversified stock portfolio is typically in the 20-60% range. Figuring out in advance "how much of a drawdown can I endure?" is the starting point of asset allocation.
The Real Reason You Need to Know MDD
Most investors fail because they sell at the bottom. During the 2008 financial crisis, many investors who experienced -40% panicked and cut their losses, and then never experienced the subsequent recovery and new highs.
Knowing your MDD in advance lets you prepare psychologically. Only those who know and accept before investing that "if I invest in the S&P 500, I may someday experience -50%" can endure that period.
Frequently Asked Questions
Q. What is a "normal" MDD?
For a diversified stock portfolio, a 20-30% MDD has historically been fairly common. An MDD of 50% or more is rare but does occur at the level of a financial crisis. For individual stocks, drops of -80% or more are not rare. "Normal" varies greatly depending on the asset's characteristics and the time period.
Q. What is the difference between MDD and volatility (standard deviation)?
Volatility represents the average size of price fluctuations, while MDD represents the single worst case. Volatility can be low yet MDD large (an asset that steadily declines), and volatility can be high yet MDD small (sharp swings that recover). For long-term investors, MDD is a more intuitive risk metric.
📋 Results are based on historical data; past returns do not guarantee future returns.
📋 This service is provided for educational purposes to help you understand investing, not as investment advice.