How are number of days for interest are calculated in FINT

Hello All,

Please clarify my doubt relating to how the SAP calculate the “number of Interest days” while calculating interest by using T Code FINT

In item interest calculation, SAP considering the posting date as the First day of interest calculation.  But while counting the number of days, it is considering the next day of the posting date.

Example: Posting date is 31.10.2013. So the first day of interest calculation is 31.10.2013.  But the number of days is calculating from  01.11.2013 instead of 31.10.2013.

Regards,

Rajesh