Hi All. i have a new question. I have to log my flight time so ive created a excell sheet to do this. as part of the competency i have to calulate totel flight time and flight time for the last 90days. So in column A i have the date (formatted 04/06/18) and in Colum G I have the flight duration (in minutes) for that date. What I want to do in column K is have the cell show the total flight time for the last 90 days from the last date in added in column A. How can I do it?