How to do group by month in a visual where it should include counts from other months before the partitioned month?

I have three columns id, subscription date and removal date. I would like to find the active subscribers count. The count should show in a visual where x axis will be subscription date(MONTH). so basically, if you are taking April in x axis, the count of id’s will be based on subscription date >= April and their removal date will be either null or greater than April.

What happens when you make a calculated field like this?

ifelse(isNull({removal_date}) OR {removal_date}>{subscription_date},{id},NULL)

Then take the count of this with you subscription_date as the x-axis