Hi all, I hope I'm not insulting anyone's intelligence by even asking this question I suspect the solution is screamingly obvious but I can't work it out so would be so grateful for any help you can provide.

I am working on a budget and different items are coded differently, for example all the security costs are coded "6516'. In column F is the amount of money that I have estimated the cost will be and issued a purchase order for. In column G is the actual amount that was invoiced. I'm now doing a column of estimated final costs that shows the actual costs incurred where possible but, when invoices haven't come in, shows the amount in the purchase order column (ie column G).

So I need the formula to calculate "where an item is coded 6516 (for example) take the amount in column F, unless that amount is zero, in which case take the amount in column G".

I hope I explained that clearly - apologies if not!!

Again - thanks so much for any help people can give me.