Start   | End    | Category    | Duration

10:00    11:00    Project 1      (end-start) = 1:00

11:00    12:00      Project 2      (end-start) = 1:00

13:00     14:00    Project 1      (end-start) = 1: 00

Now, when I attempt to create a pivot table, it was not possible to create "SUM" of duration.

"category" as row - categorize

"duration" as data - SUM of duration

Zoho sheet identifies duration value as "text" hence "SUM" is not possible.

what did i do wrong?