Determine the fraction of the year.
yearfrac( start_date, end_date, method )
start_date: (Date) The starting date.
end_date: (Date) The endng date.
method: (Date) The methodology, where 0 or omitted is US(NASD) 30/360, 1 is Actual/Actual, 2 is Actual/360, 3 is Actual/365, 4 is European 30/360.
Integer
yearfrac(today(), today() + 270, 3)
returns 0.739726