I am looking for a program which can calculate interest in a given period. Example, the principal amount is x and is subjected to interest of y% per year, what would the final amount (principal + interest) if we were to compute this from say 3/1/2009 to 28/2/2011? Well, i have to do this sort of math very often so it would of much convenience for me if i can get the final amount at the click of my mouse. Or is it possible with spreadsheet? Well, i have to admit that i know very little about programming so i am unable to write a code to do that math for me. Thank you for your time.