I have the need to calculate the timespan in years between 2 dates. Getting the number of days between is no problem; figuring out how many years 1426 days is is another question. I am able to get fairly close using days/365.25 but I don't think this is going to cut it. I am aware of the financial terms 30/360 and Actual/Actual, but don't know how to use these methods to calculate duration. Anybody have a clue?