Exit efficiency asks how much of the available move your exit kept. 100% means you sold at the best price the trade reached, 0% means you got out at the worst. It is computed from the MAE and MFE you record for each trade.
Formula
exit efficiency = (result kept + MAE) / (MFE + MAE)
left on the table = MFE − result kept (when positive)
All three are measured from the entry price in money or points. Without an MAE the simpler form is result kept / MFE, limited to the range 0 to 100%.
Example
Long at 100, worst price 99 (MAE 1 point), best price 104 (MFE 4 points), exit at 102 (2 points kept):
(2 + 1) / (4 + 1) = 60%
left on the table = 4 − 2 = 2 points
On one contract of something worth $50 per point, that is $100 left behind on a trade you will remember as a winner.
How to read it
- Below 40% on winners, consistently: exits are early. Common causes are fear after a big MAE, a target set before the trade with no reason to change it, or closing at a round number.
- Above 80% across many trades is rare and usually means very tight trailing exits, which often cost winners elsewhere.
- Look at efficiency together with the payoff ratio. An improvement in one usually costs a little of the other.
Scaling out raises the average efficiency of a strategy without trying to call the top.
In SetupBook
Analytics shows the average exit efficiency, the total left on the table, average MFE in R next to the R actually kept, and the five trades that left the most behind. The numbers appear once trades have an MFE recorded in step 2 of the form.