Excel 2007 : Supress zero value for items not inputted yet.

[evebutterly]

I have a spread sheet that contains a calculation to determine the difference between two times (estimated and actual), expressed in minutes and seconds. This formula (that I requested from this forum) shows negative times with a "-".

=IF(EstTime<ActTime,"-","") & TEXT(ABS(EstTime-ActTime),"[m]:ss")

Some results with numbers added:
Est. Act. +/-
:10 :20 :10
:30 :25 -:05
:20 :15 -:05

Here's my fondest wish: I have an estimated time for all the entries, but I don't have actuals for everything. I will be entering these over the course of several weeks. How can I surpress the solution and show nothing, if the "actuals" cell is blank?

Current output:
Est. Act. +/-
:10 (blank) -:10
:30 (blank) -:30

Desired output:
Est. Act. +/-
:10 (blank) (blank)
:30 (blank) (blank)
:20 :15 -:05

[DonkeyOte]

Run a COUNT on both - if answer < 2 then no answer viable:

=IF(COUNT(A2:B2)<2,"",REPT("-",A2>B2)&TEXT(ABS(B2-A2),"[m]:ss"))
where A2 is Est and B2 Actual

Note the above is a revised version of your formula which incidentally didn't tie out to your results ... ie you had negative numbers where Act < Est not the other way around.