create table operations (date date, cnt int);
insert into operations values 
('2019-06-02',1985), 
('2019-06-03',1577), 
('2019-06-04',1597), 
('2019-06-05',1468), 
('2019-07-06',82), 
('2019-07-08',1689), 
('2019-07-09',1556), 
('2019-07-10',1480), 
('2019-07-11',1405), 
('2019-07-12',1502); 


-- fetch some values
with t1 as (
select 
    date
    , cnt
    , strftime('%m %Y', date) as month_year
from operations)

select 
    date
    , cnt
    , sum(cnt) over (partition by month_year order by date) as cum_sum
from t1