App Development

[rcandeo]

I have this expression that works bringing amount

sum({$<YearMonth_LayOut={"$(=$(vYearMonth))"}>} amount)

But it brings only actual year/month and I need to see the months till actual month not including it. So I change the expression to

sum({$<YearMonth_LayOut={"<$(=$(vYearMonth))"}>} amount) and it brings me nothing

vYearMonth has the result = 2019/07 and I have data for YearMonth_LayOut since last year

Any idea what is wrong in  my expression please?

[rcandeo]

Unfortunatelly no numbers here

[rcandeo]

the first expression came with no numbers and the second did no respected the selection and all months were there