select 	rtrim(substr(to_char(a_date,'mm.yyyy'),1,7)),
		case	when b_date is null then '0'
				when b_date = sysdate then '1'
				when (sysdate-b_date)/30.4167 > 0 and (sysdate-b_date)/30.4167 < 1 then '1'
				else to_char(floor((sysdate-b_date)/30.4167))
		end as M,
		case	
				when substr(t,1,3) in ('999') then 'Title_1'
				when substr(t,2,2) in ('87','88') then 'Title_2'
				when substr(t,3,2) in ('11','13','14','21','23','24') then 'Title_3'
				else null 
		end as Title,
		count(*)
from 	list
where 	a_date between '01012021' and '31122021'
group by 	rtrim(substr(to_char(a_date,'mm.yyyy'),1,7)),
		case	when b_date is null then '0'
				when b_date = sysdate then '1'
				when (sysdate-b_date)/30.4167 > 0 and (sysdate-b_date)/30.4167 < 1 then '1'
				else to_char(floor((sysdate-b_date)/30.4167))
		end,
		case	
				when substr(t,1,3) in ('999') then 'Title_1'
				when substr(t,2,2) in ('87','88') then 'Title_2'
				when substr(t,3,2) in ('11','13','14','21','23','24') then 'Title_3'
				else null 
		end

coalesce(sum(count(*)) over (partition by title,a_date order by m,a_date,title
rows between unbounded preceding and current row),0) as total