No.
(haha). But seriously, this would be a script intensive thing to do. A script would have to parse a 'ps -ef' (or equiv) very quickly, looking for your executable. It would have to record the results somewhere (so as not to lose your totals if someone stops the script). Then it would have to do it all over again (and again, and again) - busy, busy.....
The risk is that between iterations, one invocation could end and another could start -net change of 0. The chance if this happening is >0.
Personally, I'd look into a 'process accounting' mechanism for your specific Unix.
-cheers