Profit factor
Gross profit from winning trades divided by gross loss from losing trades.
Formula
Profit factor = Σ winning P&L ÷ |Σ losing P&L|
How to read it
Above 1 made money; 2 means $2 won for every $1 lost.
How to use it
A quick read of edge per trade set; above about 1.5 after costs is commonly treated as robust.
Limitations
A few outsized winners can inflate it.
Also called: profit factor.