I'm looking for a macro to fill in the blank cells in the 4th column of a table with the last value above. And only in non-empty rows.

A 2 1 Apple
A 3 1
3 3 3 Banana
3 4 5
3
3 3 Cherry

Would become:

A 2 1 Apple
A 3 1 Apple
3 3 3 Banana
Banana
3 4 5 Banana
3 Banana
3 3 Cherry
Cherry

Ideas?