Fact Table Design

Hi

I have to design Fact table for the Subscriptions. In Source System, We have two Subscription table 1. Currently Active Subscriptons, 2. History which means whenever Customer Subscribe, UnSubscribe or Subscribe. there will be one row per each activity. What i need from this table is
1. how many Active Subscriptions, This is for overall
2. how many unsubscriptions in current month, There may be multiple unsubscriptions and subscripitions in this month, so only need to be considered if the unsub record has latest date.
3. how many unsubscriptions last month, There may be multiple unsubscriptions and subscripitions in the last month, so only need to be considered if the unsub record has latest date in that month.
4. how many subscriptions this month, There may be multiple unsubscriptions and subscripitions in this month, so only need to be considered if the subscripiton record has latest date.


Can you please advise how to build the fact table for this?

What i have been thinking is: I made two fact table as is in Source Systems. Is there any better solution? My concern is while generating the 2,3 and 4 above results as i need to selft join the fact table.

Thanks