PERCENTRANK formula to exclude zeros?

Hey everyone, I have tried to get this damn formula to work for awhile. I have tried various array formulas and conditional formulas, but I cannot find a way to make a percent rank formula which does NOT take into account zeros. For example:
100
200
0
0
300
400
500
0
0
600

If I do a percent rank on this row searching for 200, I want it to return 20% percentrank. However, currently when i do it it returns 56% because it is counting the zeros. any ideas? thanks everyone.

got it!
=PERCENTRANK(IF(C4:C129<>0,C4:C129),O30)
array, control shift enter when submitting, i just made an error before. replace c4:c129 with your range, o30 with your control