Count dates for the month and accumulate values

Hi pawelk3  - 

Start by creating a Date table

DateTab = ADDCOLUMNS ( CALENDARAUTO(), "Year", YEAR([Date]), "Month", MONTH([Date]))

Make a relationship between the date table and your data

Create a new measure Cumulative Sales

Cumulative Sales = TOTALYTD(COUNT(Products[ContractDate]), DateTab[Date])

This will automatically recalculate the total if a Group is selected

All:

Group G1

Hope this helps

David

Oops Sorry!  🙁  Put a parenthesis in the wrong place (remove the one directly after the first instance of DateTab[Date] on the last row, move it to the end of that row).

Cumulative Sales =
CALCULATE (
    COUNT ( Products[ContractDate] ),
    FILTER ( ALL ( DateTab ), DateTab[Date] <= MAX ( DateTab[Date] ) )
)