Calculating months between 2 dates including Decimals

Hi,

I'm trying to calculate the exact number of months between two dates. If I use MonthsBetween() formula in WEBI, it returns rounded numbers which is no good. I need exact decimals equivalent to Oracle function "MONTHS_BETWEEN".

I know a way, i.e., =DaysBetween([Start Date];[End Date])/30 but I think it's not exactly accurate. Does anyone know a better way to do the equivalent to Oracle function "MONTHS_BETWEEN"? 

FYI, I am using webi 4.0 SP5.

Thanks & Regards,

Naveen.