Aggr and If expression

[CC_Abbott]

Hello,

I'm trying to filter a dimension using another input from a selection made by the user in Qlik Sense.

I need to filter for MonthYear higher or equal to the Control StartMth.  However, my expression does not return all values.  

=aggr(if([MonthYear]>=(Min([Control StartMth])),[MonthYear]),[MonthYear])

I'm just getting introduced into Set analysis and I'm unsure if my syntax is correct.  Any help would be appreciated. Thanks

CC

[JustinDallas]

Do you have any dummy data or pictures we can look at? 

What pops out at me is  that your statement says

"If the [MonthYear] is greater than the minimum [Control StartMnth], then return the [MonthYear].  Collect these results and group by MonthYear"

That last part is kind of strange.

[CC_Abbott]

Here's a screenshot. 

I'm assuming it has something to do with the Cnt of 0 but I'M trying to filter the MonthYear dimension using the ControlStartMth field selected by the user.  Is there a better way to create a dynamic filter?

And here with selection Mar-2018 Control StartMth made