YEARFRAC /text/scalc/01/func_yearfrac.xhp YEARFRAC function

YEARFRAC

The result is the number of the years (including fractional part) between StartDate and EndDate. YEARFRAC(StartDate; EndDate [; Basis]) StartDate and EndDate are two date values.
Basis (optional) is chosen from a list of options and indicates how the year is to be calculated. Basis Calculation 0 or missing US method (NASD), 12 months of 30 days each 1 Exact number of days in months, exact number of days in year 2 Exact number of days in month, year has 360 days 3 Exact number of days in month, year has 365 days 4 European method, 12 months of 30 days each
What fraction of the year 2008 lies between 2008-01-01 and 2008-07-01? =YEARFRAC("2008-01-01"; "2008-07-01";0) returns 0.50.