Rebuilding Expectancy After a Strategy Stops Working

A strategy's performance can degrade. Market conditions change. Your edge diminishes. Understanding how to rebuild positive expectancy is crucial. This lesson details the mathematical process for identifying and correcting negative expectancy.

Identifying Expectancy Degradation

Expectancy is the average profit or loss per trade. It is calculated as:

E = (PW * AP) - (PL * AL)

Where: E = Expectancy PW = Probability of Winning (Win Rate) AP = Average Profit per Winning Trade PL = Probability of Losing (Loss Rate) = 1 - PW AL = Average Loss per Losing Trade

A strategy stops working when E becomes zero or negative. This can result from a decrease in PW, a decrease in AP, an increase in AL, or a combination.

Example: Previous Strategy Performance: PW = 0.55 (55% win rate) AP = $200 AL = $150

E = (0.55 * $200) - (0.45 * $150) E = $110 - $67.50 E = $42.50 per trade (positive expectancy)

Current Strategy Performance: PW = 0.48 (48% win rate) AP = $180 AL = $160

E = (0.48 * $180) - (0.52 * $160) E = $86.40 - $83.20 E = $3.20 per trade (positive, but significantly reduced)

If the current performance drops further: PW = 0.45 AP = $170 AL = $180

E = (0.45 * $170) - (0.55 * $180) E = $76.50 - $99.00 E = -$22.50 per trade (negative expectancy)

The strategy is now unprofitable.

Analyzing Performance Components

To rebuild expectancy, isolate which component(s) degraded. Track trades meticulously. Categorize trades by setup, time of day, volatility, or other relevant factors.

Win Rate (PW) Analysis

A declining win rate indicates the setup is less reliable. Possible causes:

1. Entry Point Degradation: The signal no longer provides the same statistical edge.
2. Market Condition Mismatch: The strategy is designed for specific volatility or trend conditions, which are no longer present.
3. Increased Competition: Other traders exploit the same edge, reducing its efficacy.

To analyze: Calculate PW for specific subsets of trades. If your overall PW dropped from 0.55 to 0.45, examine if this drop is uniform across all trade types or concentrated in one.

Example: Strategy has two main setups: Breakout (BO) and Reversal (REV). Previous 100 Trades: BO: 50 trades, 30 wins, PW_BO = 0.60 REV: 50 trades, 25 wins, PW_REV = 0.50 Overall PW = (30+25)/100 = 0.55

Current 100 Trades: BO: 50 trades, 20 wins, PW_BO = 0.40 REV: 50 trades, 25 wins, PW_REV = 0.50 Overall PW = (20+25)/100 = 0.45

Here, the BO setup caused the overall PW drop. Focus adjustments on the BO setup.

Average Profit (AP) Analysis

A declining AP suggests targets are hit less often or profit potential has shrunk. Possible causes:

1. Reduced Volatility: Price moves less, limiting profit capture.
2. Suboptimal Exits: Exiting too early, or not allowing trades to run.
3. Increased Slippage: Execution issues reduce realized profit.

To analyze: Compare the distribution of winning trade profits. Are there fewer large wins? Are most wins smaller?

Example: Previous AP = $200. Wins: 20 trades at $100, 20 trades at $200, 15 trades at $400. Total Profit = (20100) + (20200) + (15400) = $2000 + $4000 + $6000 = $12,000 AP = $12,000 / 55 = $218.18

Current AP = $170. Wins: 30 trades at $100, 10 trades at $200, 5 trades at $400. Total Profit = (30100) + (10200) + (5400) = $3000 + $2000 + $2000 = $7,000 AP = $7,000 / 45 = $155.56

The reduction in higher-profit trades ($400 wins) and increase in lower-profit trades ($100 wins) caused AP to drop.

Average Loss (AL) Analysis

An increasing AL indicates losses are larger or stop-loss placement is ineffective. Possible causes:

1. Wider Price Swings: Stops are hit more frequently or require wider placement.
2. Delayed Exits: Holding losing trades past the stop-loss level.
3. Increased Slippage: Execution issues increase realized loss.

To analyze: Compare the distribution of losing trade losses. Are there more large losses?

Example: Previous AL = $150. Losses: 20 trades at $100, 20 trades at $150, 15 trades at $200. Total Loss = (20100) + (20150) + (15200) = $2000 + $3000 + $3000 = $8,000 AL = $8,000 / 55 = $145.45

Current AL = $180. Losses: 10 trades at $100, 20 trades at $200, 25 trades at $250. Total Loss = (10100) + (20200) + (25250) = $1000 + $4000 + $6250 = $11,250 AL = $11,250 / 55 = $204.55

The increase in larger losses ($200 and $250) contributed to the higher AL.

Rebuilding Expectancy: Actionable Steps

Once the degrading component is identified, implement targeted adjustments.

Adjusting Win Rate (PW)

1. Refine Entry Criteria: Add filters. For example, if a breakout strategy performs poorly in low volatility, add a minimum Average True Range (ATR) filter.
   • Example: Trading futures contract ES. Previous entry: Break of 4500.00. New entry: Break of 4500.00 only if 14-period ATR > 4 points.
2. Increase Confirmation: Require additional indicators or price action confirmation before entry.
   • Example: Instead of entering on a single candlestick pattern, require a subsequent candle close in the direction of the trade.
3. Avoid Specific Market Conditions: If a setup fails during specific times (e.g., lunch hour, pre-market), cease trading during those periods.

Adjusting Average Profit (AP)

1. Optimize Exit Strategy:
   • Trailing Stops: Implement a trailing stop to capture larger moves.
     • Example: Buy 100 shares of XYZ at $50. Initial target $51. Instead, trail stop by $0.20. If price hits $51.50, stop moves to $51.30.
   • Multiple Targets: Scale out of positions at different price levels.
     • Example: Buy 100 shares. Sell 50 at $0.50 profit, hold 50 for $1.00 profit. This balances profit taking with potential for larger gains.
2. Increase Position Size on High-Conviction Trades: If certain setups consistently yield larger profits, allocate more capital to them. This increases overall AP without changing the individual trade AP.
   • Example: Setup A has AP of $300. Setup B has AP of $150. If Setup A occurs, trade 2 contracts instead of 1.

Adjusting Average Loss (AL)

1. Strict Stop-Loss Enforcement: Do not move stop-losses further away. Exit at the predetermined level.
2. Tighten Stop-Losses (if appropriate): If initial analysis shows stops are too wide, reduce