YEARFRAC

The YEARFRAC function calculates the number of years, including fractional years, between the dates as a decimal fraction.

This function can be useful in financial calculations to determine proportional amounts of interest, insurance premiums, and rent payments for a partial annual period.

Syntax

YEARFRAC(start_date, end_date, [calculation_method])

Argument	Description	Permitted values
start_date	Start date of the calculation period	Date or reference to a cell containing the date
end_date	End date of the calculation period	Date or reference to a cell containing the date
[calculation_method]	0 (US, NASD) — all months are rounded to 30 days and all years to 360 days. Used by default. 1 — without rounding 2 — months are not rounded, years are rounded to 360 days 3 — months are not rounded, years are rounded to 365 days 4 (EU) — all months are rounded to 30 days and all years to 360 days	0, 1, 2, 3, 4

Examples of use

Calculation of the fraction of the year between January 1, 2023, and July 1, 2023, using calculation method 1 (actual days/actual days in the year):

=YEARFRAC("01/01/2023", "07/01/2023", 1)

Result: a value approximately equal to 0.5.

Calculation of the fraction of the year between January 1, 2023, and December 31, 2023, based on 0 (US 30/360 method):

=YEARFRAC("01/01/2023", "12.31.2023")

Result: 1.

Notes

Make sure that the cells containing dates have the correct date format for proper functioning.