[Quantlib-users] YearFraction method

[Kishore K. <rkr...@gm...>]

Hi,
I am using quantlib's year fraction method in Python as below:
t0 = ql_day_count.yearFraction(dt1, dt2).  My day count is Actual Actual
(ISMA) , I get a number that is significantly different from that in
Excel.  For example,  dt1 is 2021-02-17 and dt2 is 2027-06-01. Quantlib
returns a value of 6.25. Excel on the other hand returns a value of 6.285.
I am using the basis as 1 (Actual/Actual) in Excel. I am trying to
understand the difference. Would appreciate some help.
Thanks
Krish