Extension of IFERROR/VLOOKUP formula help needed.

Hi there,

If you could please look at the tab "Publisher sumif summary" and at the "Q" column. There is already a formula in place which returns a number from column B in the "Publisher Control Sheet".

If you look at Column B in the "publisher control sheet", you can see that for some of the companies in column A there is no number. Instead, there is a number in Column C where there is no number for column B.

The problem at the moment is that I don't know how to get the data from Column C factored into the equation, which I will describe below

Essentially, i need the formula in the Q column of the "Publisher sumif summary" to return "((Column M number (impressions) /1000)* Column C number) with the column C number coming from the "Publisher control sheet" tab. It needs to only do this where there is no number in column B, and i've no idea how to add this function!

I hope this makes sense, not the easiest one to explain today!

Any help much appreciated.

Regards & thanks

Roger.