correct when choosing max

to correct the error of choosing the maximum.. it is an oscillator that looks for wave three taking -40%.. all that works well for me.. to look for wave three I ask for a minimum of 8 bars, and it takes the bar as a maximum 8 onwards, what should be is that if there is a maximum before bar 8, take that maximum to calculate the -40%, taking into account that it requires a maximum of 8 bars to look for wave three