To find your longest losing run of losses to a 99% confidence level do as follows;

=sum(1-(Losing % ^(to the power of) N (N=number of Losses) this will provide a % when you get to 99% this should equate to your longest losing run

example win%= .092 Losing % .908

=sum(1-(.908^5losses)=.382
=sum(1-(.908^17losses)=.806

Cheers