SUM() ignores text, while the + operator will coerce its text arguments
to numeric if it can.

Try coercing your data to actual numeric values (which is how XL stores
times - as fractional days) by copying an empty cell, selecting your
values, choosing Edit/Paste Special, selecting the Values and Add radio
buttons, then clicking OK. Format the result as time.



In article ,
AJG wrote:

Is there anyone out there who knows why the SUM function won't work, but
manual addition will?