New to Microsoft Excel? Looking for a tip? How about a tip so mind-blowingly useful as to qualify as a magic trick? You're in luck. In this MS Excel tutorial from ExcelIsFun, the 617th installment in their series of digital spreadsheet magic tricks, you'll learn how see a SUMIFS and SUMPRODUCT functions formula to sum the fiscal year's sales when the year does not end on December 31st. Also see a formula for year-over-year percentage change.