The formula in cell A6 uses Excels DATE function to ensure that the date 10152015 is entered and stored as a date value. Select a blank cell you will return the week number enter this formula. First the DATE function creates the date 5.
Well do this by writing a different kind of formula shown above.
Regardless of the format used the formula should remain the same. Determine leap and non-leap years - two Date formulas to pin down leap years in Excel. Enter the number of days to add or subtract in column B. SUM A125 Format column B1 as a date.