Increment a variable through a transition

Is it possible to increment a variable through a workflowtransition? I am trying to setup a parallel approval workflow andwould like to use a variable to define when all voting conditionshave been met.

Variable:
Votes

Expressions already tried:
Add(1,%Votes%)
=1+%var_Votes%
1+%var_Votes%

What is the proper syntax to add one to the existing variable?

Thanks,
Stephen MooreSolidworksSolidworks Pdm enterprise Pdm