Counting Time dimension members having data

I have a time dimension structured as Year > Quarter > Month. Dimension name is [Time]. Tree Name is [Time Tree]

I have a measure called [Revenue USD].

I am making a report for a Quarter wherein I have the Revenue reported as 

Q1 : $300

Q2 : $200

Now I need to show how many months comprise this revenue. For example, in above reporting, Q1 revenue is for 3 months while Q2 is only for 2 months

Q1 : $300 : 3 months

Q2 : $200 : 2 months

How do I get a count of months, where the revenue > 0?