with z as (
    select max(monthly) as r from mrr_data
), y as (
    select MONTHLY as m, NEW_MRR + EXPANSION_MRR - DOWNGRADE_MRR - CHURN_MRR as n,
    rank() over (order by monthly)
    from MRR_DATA
    union all
    select date((select r from z), '+1 months') , 0, (select count(*) from mrr_data) + 1
)
select y1.m as YM, sum(y2.n)-y1.n as MRR
from y as y1 inner join y as y2 on y1.m>=y2.m
group by y1.m