You can also create serial numbers
Excel Date Conversion
When you use dates in your Microsoft Excel workbooks, you may want to use the serial numbers for those dates. You can use them in formulas or for calculations instead of the dates themselves.
We'll show you how to convert dates to numbers, specifically serial numbers, in Excel. The method you use depends on how Excel stores dates in your worksheet; in short, how it formats them.
Before you use any of the methods below to convert your date to a serial number, you should determine how the date is formatted. By default, a date you enter into Excel is formatted as a date, which is technically a numeric value. However, there may be instances where you enter, convert, or import dates that end up being formatted as text values.
