I’ve just spent half an hour with Excel, trying to get a formula to calculate whether a date is later (or larger) than another date.
The cell F1=1/1/2013 and the date in cell C2 is variable.
Now this usually works, however in this case the data is an exported report and the date values in column C is formatted to DATE format same as cell F1.
The calculation formula is correct but the result does not work correctly unless selecting the variable cell C2 and clicking ENTER. Now if you have only a few cells to goto each and clicking ENTER is fine, but if you have several hundred or thousands of cells to go through then doing this is prohibitive.
SOLUTION: Save your spreadsheet as .csv then open the .csv file and save it again as an Excel spreadsheet file and re-enter the formula.