Rolling expectancy and 12-month return
Shows recent performance change through the latest 40 trades on a trading account or the latest 12 months on an investment account.
For a trading account, the expectancy line is the average net result of the latest 40 closed trades. Win rate appears beside it, while the ±SEM (standard error of the mean) band shows uncertainty around the average: a wider band means more variation inside the window. The first points appear after roughly 60 closed trades: the 40-trade window plus a minimum history tail.
For an investment account, the tab switches to rolling 12-month return. Each point answers what the TWR return was for the year ending there; dividends and coupons are already reflected in NAV. The chart needs at least 18 monthly observations.
Both branches can reveal change sooner than a whole-history metric. They do not predict the next period: one move below zero or one strong year is a prompt to check context, not a verdict on the strategy.
Example: the latest 40 trades total +$400 and 22 are profitable. Expectancy at that point is +$10 per trade and win rate is 55%; the band's width depends on the spread of those 40 results.
Look for direction across several neighboring points, the band width in the trading branch, and the length of the history. This makes a random jump less likely to be mistaken for a durable shift.
How we compute it
In the trading branch, we sort trades by close time and calculate average net result, win rate and a band from the mean minus the standard error of the mean to the mean plus the standard error of the mean for every 40-trade window. Publication starts after 60 trades. In the investment branch, we combine monthly TWR returns over each trailing 12-month window so each month's result applies to the already changed base; the chart appears after at least 18 months of data.