I'm using this function to calculate date difference, but just stumbled upon
something that's making me think it's wrong.

Here it is: =DATEDIF(B3,C3,"y") & " years, " & DATEDIF(B3,C3,"ym") & "
months, " & DATEDIF(B3,C3,"md") & " days"

It seemed to work fine until I entered the same date into the two cells, and
what returned was: 0 years, 0 months, 0 days. This seems odd to me. Shouldn't
that be 0 years, 0 months, 1 days. Why doesn't the function count the "zero
date" as one? How should I modify it so I get an accurate result?

Thanks