Maximum Drawdown is the largest percentage decline from a peak to a subsequent trough in a strategy’s performance history. It represents the single worst loss an investor would have experienced if they had entered at the peak and held through the lowest point. It is the most widely cited risk metric in strategy evaluation.

The No-BS Truth: MDD is the least complete single-number risk metric available. It tells you the depth of the worst event that occurred—in the one historical path that actually happened. It provides no information about how long recovery took, how frequently smaller drawdowns occurred, or what the distribution of losses looks like across the full history. Two strategies with identical MDDs can have completely different lived risk profiles. Relying on MDD alone is not risk management—it is risk summarization.

The Underwater Period is the total time a strategy spends below its previous all-time high equity level. It begins when the strategy experiences any decline from a peak and ends only when a new peak is established. It encompasses both the drawdown phase and the recovery phase—the full duration during which capital is not at its maximum realized value.

The No-BS Truth: The underwater period is often a more psychologically relevant measure of risk than MDD, because it captures the full duration of the adverse experience rather than just its depth. A strategy that spends 18 months recovering from a 15% drawdown inflicts more sustained psychological damage than one that spends three weeks recovering from a 20% drawdown. The Ulcer Index formalizes this intuition by combining depth and duration into a single measure of the actual stress burden of holding a strategy.

The Ulcer Index is a risk metric that measures the depth and duration of drawdowns by computing the root mean square of all percentage drawdowns over a given period. Unlike standard deviation, which treats upside and downside variation symmetrically, the Ulcer Index captures only the downside experience—specifically, how deep and how long the underwater periods are across the full history of the strategy.

The No-BS Truth: The Ulcer Index is the most honest available measure of the psychological cost of holding a strategy. A strategy with a low Ulcer Index spends little time underwater and recovers quickly from declines. A strategy with a high Ulcer Index may produce strong final returns, but requires the operator to endure extended periods of stagnation—the conditions most likely to produce abandonment. Ordertune prioritizes the Ulcer Index over MDD as a risk criterion precisely because it captures the lived experience rather than the outer boundary.

Stagnation Risk is the risk that capital remains committed to recovering from a prior loss for an extended period, during which it cannot participate in new growth opportunities or compound toward new highs. It is the opportunity cost of the recovery phase—the return the capital would have generated if it had been deployed productively rather than clawing back a previous decline.

The No-BS Truth: Stagnation risk is invisible in MDD statistics and rarely discussed in standard risk frameworks. Yet it is one of the most common mechanisms through which systematic traders underperform their theoretical models. An account that spends 24 months recovering from a drawdown has not just lost the depth of the drawdown—it has also lost 24 months of compounding at the strategy’s normal expected rate. The total cost is the drawdown depth plus the foregone compounding during the recovery. MDD captures neither.

The Drawdown Distribution is the full statistical characterization of a strategy’s loss profile across its history—including the frequency of drawdown events at each magnitude level, the distribution of recovery durations, the median and maximum underwater periods, and the proportion of time spent at or near all-time highs. It is the complete picture of which MDD is a single data point.

The No-BS Truth: A strategy with a favorable drawdown distribution—frequent small drawdowns that recover quickly, rare large drawdowns with defined recovery mechanisms—is structurally different from one with the same MDD but a more adverse distribution. The former is psychologically manageable because most adverse events are brief and recoverable. The latter may produce the same peak loss but inflicts it through a pattern of events that drives abandonment long before the maximum is reached. Distribution analysis is what separates informed risk assessment from headline-number selection.

MDD measures only the single worst peak-to-trough decline in a strategy’s history—one data point from one historical path. It provides no information about how long the recovery took, how frequently smaller drawdowns occurred, or what the distribution of loss events looks like across the full record. Two strategies with identical MDDs can have completely different lived risk profiles: one recovers in three weeks, the other takes three years. The number is the same; the experience of holding them is not. Risk assessment that relies solely on MDD is measuring the boundary of the worst event while remaining blind to the structure of every other adverse event in the strategy’s history.

The Ulcer Index combines drawdown depth and drawdown duration into a single metric by computing the root mean square of all percentage drawdowns over a period. It captures how long capital spends underwater and how deep those underwater periods are—not just the single deepest point. A strategy with frequent, persistent drawdowns that barely approach the MDD can have a much higher Ulcer Index than one with a single deep event that recovers quickly. The Ulcer Index reflects the actual psychological cost of holding the strategy across its full history, not the worst moment in isolation.

Stagnation risk operates through two channels simultaneously. The first is the direct cost: capital committed to recovering from a drawdown is not compounding toward new highs. The second is the opportunity cost: every month spent in recovery is a month during which the strategy’s normal expected return is not being generated. A strategy that spends 24 months recovering from a 20% drawdown has not just lost 20%—it has lost 20% plus 24 months of compounding at the strategy’s average annual rate. MDD captures the first cost only. The Ulcer Index partially captures both through its duration weighting. Full stagnation risk assessment requires computing the foregone compounding across all recovery periods in the strategy’s history.

Evaluate at minimum four metrics: the MDD (the outer boundary), the Ulcer Index (the lived stress burden), the maximum underwater duration (the longest recovery period), and the percentage of time spent at all-time highs (the proportion of time the strategy is actively compounding rather than recovering). Together these four numbers provide a meaningful picture of the strategy’s lived risk profile. Strategies that perform well on all four—limited depth, low Ulcer Index, short maximum recovery, high proportion of time at peaks—are structurally more sustainable than those that optimize for MDD alone. Position size should be calibrated to the Ulcer Index and maximum underwater duration, not just the MDD.

Ordertune displays the full underwater structure of the Protocol’s performance rather than selecting the most favorable single metric. This includes the equity curve with drawdown periods clearly marked, the Ulcer Index as a primary risk metric alongside the MDD, and the drawdown comparison against the Nasdaq 100 benchmark across the full history. The goal is to give every subscriber the information needed to evaluate whether the strategy’s actual risk profile—not just its worst single event—is compatible with their psychological tolerance and financial circumstances. We do not smooth the data, select favorable windows, or present summary statistics in isolation. You see the full picture before you commit capital.