Value becomes 0 on month selection

[Iwin]

Hi all,

I have a table to show revenue .The field used in Month Year Column is Project Start Month which is linked to all other tables.However the fields used in Year,Quarter and Month are present in a data island Master Cal table.

Issue is when I there is no month selected value is showing in March as 0 ,however when March is selected in Month ,correct value appears.

Value becomes 0 on no month selection

Value missing here

Value visible on month selection

Value Present when March is selected

Also when 2 months are selected together ,sum of those months are coming in Apr 21 column.

It should show up as Mar21 -14666 and Apr21-7046

Expression used in Revenue is 

Sum( {<PROJECT_START_MONTH={"<=$(=addmonths(monthend(max(CALDATE)),1))>=$(=monthstart(max(CALDATE)))"},CLASS_CATEGORY={'BILL_TO_REV'},CLASS_CODE1={'BILL_EQUAL_TO_REV'}>}[BILL AMOUNT NEW])

What changes should I make here so that value appears correctly without month selection as well when 2 months are selected?

[IamAlbinAntony]

Try this,

Sum( {<PROJECT_START_MONTH={">=$(=monthstart(max(CALDATE)))<=$(=addmonths(monthend(max(CALDATE)),1))"},CLASS_CATEGORY={'BILL_TO_REV'},CLASS_CODE1={'BILL_EQUAL_TO_REV'}>}[BILL AMOUNT NEW])

[Iwin]

It is showing the same result as before in both the cases :without month selection and when 2 month are selected.