You can use the 1904 date system to display negative time, however, this
will affect any dates you already have entered in your file. They will be
off by 4 years (1462 days). This can be a significant drawback! You can fix
this side effect but it may not be worth the trouble.

ToolsOptionsCalculation1904 date system

Then you'd have to subtract 1462 days from the dates that changed.

Other options:

Use decimal values instead of time formatted values.
You can display a negative time as TEXT but this may affect any downstream
calculations.

--
Biff
Microsoft Excel MVP


"dknorwood" wrote in message
...
I have a spread sheet that I use for time comparisons on a project. There
are target and actual times that get compared. I want to be able to show
the
resulting difference as a positive or negative value. For example:

Target Time: 9:00 AM
Actual Time: 9:01:25 AM

I would like to be able to show tha result as + 01:45

I also need to account for the other situation as well:

Target Time: 9:00 AM
Actual Time: 8:58:25 AM

I would like thsi result to show as - 01:35

Any help would be most appreciated. I can definitely get the calaulation
to
run ok, but I have not yet found a way to format the result in the desired
fashion.

dknorwood