Sure. The formula involved doesn't involve any "big" functions, so it works for pretty much any number. The formula for the "Win Rate Area" is:
Code:
=ROUND((A2*$G$1+NORMSINV(0.025)*SQRT(A2*$G$1*(1-$G$1)))/A2*100,2)&"%-"&ROUND((A2*$G$1-NORMSINV(0.025)*SQRT(A2*$G$1*(1-$G$1)))/A2*100,2)&"%"where A2 is the cell where you put your number of trials, and G1 is a fixed cell containing the actual win rate.