Excel treats time as numbers. So, 1 day = 1. 1 hour = 1/24.

40 hours = 40/24.

So, sum of times - (40/24) = answer. format as hours:mins.

"Paul Black" wrote:

Hi everyone,

I have a column of hours and minutes like 19:55, 07:12, 20:12 etc. I
have also managed to add up the total number of hours and minutes for
each week. I have used a custom format of [hh]:mm which works well.
Now, say the weekly working hours are 40, i would like to take the
total weekly hours and minutes they actuially worked and subtract what
hours they should have worked, i.e. 40.
So the formula would be something like ...

total hours and minutes actually worked - 40

Thanks in Advance.
All the Best
Paul