Good Afternoon

I was wondering if anyone can help me I have to following IF statement but it does not seem to work at all 

IF(AND(C7="0",F7="0"),0,IF(AND(C7>=1,((F7-C7)/C7),(F7/F7))))

EG if cell C7 and F7 both are zero I want to return a zero, However if cell C7 is equal to or grater than one I want the formula to calculate out

This is not working for some reason, any help would be appreciated

Thanks
CraigieL