Calculating MTD values dynamically

[scw]

I am trying to build a MTD measure in QlikSense. The expression that I am using is –

rangesum(above( sum({<MTD={'1'}>}[Attendee Amount]),0,rowno()))

This does give the MTD numbers for the current month but in the sheet I have a drop down for months. If I choose any month other than the latest month I don’t get any values. Any ideas how I can make the expression dynamic?

[Gysbert_Wassenaar]

How is the MTD field created? I suspect that only the days current month get a value 1 for that field. If that's the case then you can't use it for what you want to do. You can try creating and using an AsOf table like described in this document: Calculating rolling n-period totals, averages or other aggregations