I have a spreadsheet which has a name in Column A headed "Fullname", a column header "Amt" which contains a monthy payment amount and then 9 columns headed "Sept,Oct,Nov etc These month columns contain a "Y" when the amount is paid. I want to identify people whose payment is overdue. Thus, we are in November so I want to list those who have not paid in September or October. (Anyone who has paid Oct MUST have already paid Sep) Next month it will be those who have not paid in either Sep Oct or Nov and so on. Can I do it in Excel?