That's certainly a working solution, however if you'd like a simpler option, try a For loop:
Start Loop : Repeat 50 times
Scroll mouse wheel forward 1 click
Pause 0.05 seconds
End Loop
That's under "Other >", "Advanced", "Add a Loop Start", "Repeat Certain Number of Time (For Loop)"
As a side note, the "Small Integer" datatype is deprecated. "Integer" should be used instead (it can be decremented using the "Computed value" option set to "Subtract" and "Compute against a value" set to 1. The For loop above doesn't require manually decrementing a variable value at all though)