Hi, Janie,

Use this Microsoft web link for the complete explanation:

http://office.microsoft.com/en-us/ex...093441033.aspx

The 4 basis options cover various different accounting approaches to
breaking down accounting (e.g. 30 day accounting months / 365 days/year vs.
the actual number of days in a year, which is different on a leap year)

Hope this helps.

Regards,
Marty S.

"Janie" wrote:

I was trying to explain the YEARFRAC function to someone. I use it and
always omit the Basis. But I couldn't really explain what the different
Basis values mean. Oh, I know it determines how the days are counted .. but
exactly HOW???

The online help doesn't explain the value at all, and so I was hoping
someone could give me a good definition on how to determine which Basis one
should use under which circumstances.

Thankx for any insight.