Calculates the fraction of a year represented by the number of whole days from start_date to end_date. Use the YEARFRAC function to identify the proportion of a whole year's benefits or obligations to assign to a specific term.
Dates should be entered by using the DATE function, or as results of other formulas or functions. For example, use =DATE(2008,5,23) for the 23rd day of May, 2008. Problems might occur if dates are entered as text.
A date that represents the first, or starting, date of the period.
A date that represents the last, or ending, date of the period.
The kind of day count basis to use.
Excel stores dates as sequential serial numbers so they can be used in calculations. By default, January 1, 1900 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39,448 days after January 1, 1900.
To make the following example easier to understand, you can copy the data to a blank sheet and then enter the function underneath the data. Do not select the row or column headings (1, 2, 3... A, B, C...) when you copy the sample data to a blank sheet.