Expectancy — P&L

Expected value per trade in account currency. Average net P&L across all trades.

Computed from
Trades list
Scope
Single report
Range
Any real number
Direction
Higher is better
Basis

Expectancy is the bottom line of a trading edge: the average amount you can expect to make (or lose) per trade, over many trades. It rolls win rate and payoff ratio into one number — and if it's positive, the system makes money in the long run.

How it's calculated

Expectancy = (Win% × AvgWin) − (Loss% × AvgLoss)
          = mean(net P&L per trade)
Win% / Loss%
share of winning / losing trades
AvgWin / AvgLoss
average size of a win / a loss (loss as a positive magnitude)
In this product: Both lines give the same number: the top builds it from win rate and average sizes; the bottom just says "add up every trade's result and divide by the number of trades." Same answer, two routes. You can also measure expectancy in % return or in pips instead of dollars — those versions ignore how big your positions were, so you can fairly compare two strategies, or two different currency pairs, side by side. (Pros often quote expectancy in R-multiples — profit per unit of risk taken, e.g. "+0.2R per trade"; the pips% version is the closest sizing-neutral equivalent here.)

What it tells you

Expectancy is the per-trade "edge." Combined with how many trades you take, it gives a first-order estimate of expected income:

Expected weekly result ≈ Expectancy × trades per week

This is an estimate, not a forecast — it assumes the edge, the trade frequency, and the position sizing all keep holding (see Pitfalls).

Worked example

A system wins 45% of trades, with an average win of +$300 and an average loss of −$180:

Expectancy = 0.45 × 300 − 0.55 × 180 = 135 − 99 = +$36 per trade

At 40 trades a week that averages to roughly +$1,440/week — but read that as a long-run mean, not a paycheck. The real path swings hard around it: losing streaks are normal, and a positive-expectancy system can still ruin an over-sized account before the average ever shows up. It also assumes the historical edge keeps working (see Pitfalls).

Pitfalls

Pitfalls & caveats
  • It's a rear-view mirror. Expectancy is measured on trades that already closed. A positive number is evidence of a past edge, not a promise of a future one — edges decay as markets, crowding, and spread conditions change. The more recent and the more numerous the sample, the more you can lean on it; a thin or stale record projects poorly.
  • An average hides the variance — and the risk of ruin. A positive expectancy still comes with losing streaks, and bad sizing can ruin the account before the long-run average ever arrives. Size positions so you survive the streaks (see Kelly).
  • Driven by outliers. A handful of huge winners can carry expectancy; if they don't repeat, the edge evaporates. Cross-check profit concentration — and check when the edge shows up, since a system that earns its whole year in a few sessions is far harder to trade than its expectancy suggests.
  • Costs scale with frequency. The ×trades multiplier in the projection multiplies costs too — slippage and spread that look tiny per trade add up at 40 trades/week, and live fills rarely match a clean historical record.
  • Which version you use matters. The $-version weights big positions more; the return-% and pips% versions ignore position size. Use the size-neutral versions when comparing strategies.

Expectancy vs profit factor

Both summarize the trade distribution. Profit factor is a ratio (total wins ÷ total losses, scale-free); expectancy is an amount (per-trade, in real units). Profit factor tells you the edge's quality; expectancy times frequency tells you the edge's size in money.

Related metrics