Nested IF formula with wildcard

[AL0905]

I am setting up a spreadsheet to collect monthly figures. Of these figures I want excel to automatically calculate a percentage using two figures. I have this formula just fine. I want to have the formula present for all future months so that when I input the figures it automatically calculates the percentage for me. However for future months I don't want to see the error message where there aren't any figures to calculate the percentage yet as it makes my spreadsheet look messy. I have figured to get around this to use an IFERROR and make errors 0 and hide all 0 values. For months were I have input figures and there are no figures I want that 0 value to be 100. Some background: the percentage I am calculating is % waste diverted from landfill. So on months where the value is 0 - technically 100% of waste has been diverted from landfill as no waste was produced. So now I'm thinking of using nested IF formulas. What I want is IF ERROR(yes = 0) (no = (D17/D16)*100) and then another IF when the first IF is yes =0, then if there is any figure in another cell (D13=waste to landfill) EVEN if that figure is zero i.e. Wildcard ? (yes =100) (no=0) as if there is no figure in D13 it means there are no figures from that month yet. This is what I have but it is very wrong =IFERROR((D17/16)*100,0),IF(COUNTIF(D13,"?"),100,0). I really hope this makes sense. Please help!

 

[FormR]

Hi, welcome to the forum!

Not sure entirely but it sounds like this might be what you want:

=IF(D13="",0,IF(D16=0,100,(D17/D16)*100))