Drawdown Severity Score Methodology
The Drawdown Severity Score is a proprietary metric that measures how statistically unusual a current price decline is compared to an asset's historical drawdown pattern. This page explains the methodology behind the score with full transparency.
Overview
Most investors look at raw drawdown percentages to gauge how severe a price decline is. The problem: a 20% drop means something very different for a volatile growth stock than for a stable blue-chip. The Drawdown Severity Score solves this by normalizing each asset's current drawdown against its own historical drawdown distribution.
The result is a single number—typically between 0 and 12+—that tells you at a glance how unusual the current decline is for that specific asset. A score of 0 means the asset is at or near its all-time high. A score of 8+ means the current drawdown is extremely rare by historical standards, occurring only a handful of times in the asset's entire price history.
The score exists to help long-term investors filter out routine noise and focus only on the drawdowns that are truly statistically significant for each asset they follow.
How the Score Is Calculated
The Drawdown Severity Score is computed through a five-step statistical process applied independently to each asset:
- Calculate the current drawdown percentage. We determine the asset's all-time high closing price and express the current price as a percentage decline from that peak. For example, if a stock's all-time high is $200 and the current price is $160, the current drawdown is -20%.
- Build a historical distribution of drawdowns. Using up to 40 years of daily closing price data, we calculate the drawdown percentage for every single trading day in the asset's history. This produces a comprehensive distribution of how far below its running all-time high the asset has been on any given day.
- Calculate the mean and standard deviation. From the historical drawdown distribution, we compute the mean (average drawdown) and the standard deviation (a measure of how much the drawdowns vary). These two statistics summarize the asset's typical drawdown behavior.
- Express the current drawdown as standard deviations from the mean. We take the current drawdown percentage, subtract the historical mean, and divide by the standard deviation. This z-score tells us how many standard deviations the current drawdown is from the asset's average drawdown.
- Apply normalization to produce the final score. The raw z-score is normalized to produce the final Drawdown Severity Score on a 0–12+ scale. Scores near 0 indicate the asset is at or near its all-time high, while scores above 8 indicate historically rare drawdowns.
Score Interpretation
The Drawdown Severity Score maps to six zones, each representing a different level of statistical significance:
| Score | Zone | Label | Interpretation |
|---|---|---|---|
| 0–0.5 | Green | At/Near ATH | The asset is at or very near its all-time high. No meaningful drawdown. |
| 0.5–2 | Green | Typical | Normal fluctuation within the asset's historical range. Nothing unusual. |
| 2–3 | Yellow | Slightly Elevated | Exceeding typical range. Worth monitoring but not yet rare. |
| 3–5 | Yellow | Elevated | Noticeably elevated drawdown relative to history. Attention recommended. Potential value emerging. |
| 5–8 | Red | Significant / Strong | Rare drawdown depth. Historically unusual for this asset. May represent a significant opportunity for long-term investors. |
| 8+ | Red | Extreme / Historic | Extremely rare or historically unprecedented drawdown. Crisis-level discounts that occur only a handful of times in an asset's full price history. |
Why Volatility-Adjusted?
A raw drawdown percentage is a poor measure of severity in isolation. Consider two assets:
- Stock A is a stable utility company that has rarely dropped more than 15% from its peak in 30 years of trading history.
- Stock B is a volatile growth stock that routinely swings 30–40% from its highs as part of normal price action.
If both stocks are currently down 20%, the raw percentage is identical. But the significance is very different: for Stock A, a 20% drop is a historically extreme event. For Stock B, it is a routine fluctuation.
By adjusting for each asset's own volatility profile (captured in its historical standard deviation), the Drawdown Severity Score produces comparable numbers across different assets. A score of 5.0 always means “this drawdown is unusually severe for this specific asset,” whether the underlying percentage is 12% or 45%.
Data Sources
All price data used to compute the Drawdown Severity Score is sourced from Yahoo Finance historical data feeds. We use adjusted daily closing prices to account for stock splits, dividends, and other corporate actions.
For each asset, we retrieve up to 40 years of daily price data (when available). Newer assets such as recent IPOs or cryptocurrencies use all available history. More historical data generally produces a more robust and reliable severity score.
Update Frequency
Severity scores are recalculated daily after market close. Our system begins processing updated prices at approximately 4:15 PM ET each trading day. All monitored assets are typically updated within a few hours of market close.
Cryptocurrency scores are updated seven days a week since crypto markets trade continuously.
Limitations
We believe in full transparency about what the Drawdown Severity Score does and does not do:
- Not a buy or sell signal. The score measures statistical rarity, not future returns. A high score does not mean the price will recover, and a low score does not mean the price will fall.
- Past performance is not indicative of future results. The score is based entirely on historical price patterns. Markets can behave differently in the future than they have in the past.
- Does not account for fundamental changes. If a company's business model has fundamentally deteriorated, a high severity score may not indicate an opportunity. Always combine quantitative signals with fundamental analysis.
- Limited by available history. Assets with short price histories (e.g., recent IPOs) have less reliable scores because the statistical distribution is based on a smaller sample size.
- Not investment advice. DrawdownAlerts is an informational tool. We do not provide personalized investment advice. Consult a qualified financial advisor before making investment decisions.
Frequently Asked Questions
Is the Severity Score a buy signal?
No. The Drawdown Severity Score measures how statistically unusual a current drawdown is relative to an asset's own history. It is not investment advice and should not be interpreted as a buy, sell, or hold recommendation. A high score indicates that the current drawdown is rare by historical standards, but it does not guarantee a recovery or predict future performance. Always conduct your own research and consider fundamentals before making investment decisions.
How far back does the historical data go?
The score uses up to 40 years of daily closing price data from Yahoo Finance, depending on the asset's available history. For newer stocks or cryptocurrencies, the calculation uses all available data. More historical data generally produces more reliable severity scores because the statistical distribution is based on a larger sample.
Why does the same drawdown percentage produce different scores for different stocks?
Because the score is volatility-adjusted. A 20% drawdown might be routine for a volatile tech stock that regularly swings 30–40%, but it would be historically extreme for a stable blue-chip that rarely drops more than 15%. The Severity Score normalizes each drawdown relative to the asset's own historical pattern, so a score of 5.0 always means “this is unusually severe for this specific asset”—regardless of the raw percentage.