If you put the three DATEDIF functions in separate columns, one for
year, month and day (without the text labels), then you will find it
easier to total them, with appropriate carry forwards.

If you use =B1-A1 in C1 this will give you the number of days
difference, so you can total these easily and then split into years,
months and days. You might like to keep column C like this (you can
hide the column) and then format column D to give the display how you
have it now in C.

Hope this helps.

Pete

On May 17, 6:13*pm, kathi wrote:
I have two (A&B) columns with dates in each
I them have (C) with the formula =DATEDIF(A6,B6,"y") & " years, " &
DATEDIF(A6,B6,"ym") & " months, " & DATEDIF(A6,B6,"md") & " days"
I need to total column (C)
OR
I have also revised it so that (C) is =B1-A1 * resulting in a number string
and then formatting the cell to read yy " years, " mm " months, " dd " days"
but I still can't get a total of all these years...............