Just after some clarification on calculating the profit on a fictional set of bets. So take the following numbers taken from betting BFSP based on backing them for 1 unit, and tell me have I got my working correct.

Bets - 100
Wins - 20
Losers - 80
Return 85
SR - 20%

So working out the lay profit, are the below figures correct?

-80 (lay winners) minus 5% would be your total lay return, so 76 unit return
-your payout would be 85 minus the number of selections so 65 units paid out

therefore your profit if you were to lay those would be 11 units, is this correct?