Q&A for students, teachers, and linguists wanting to discuss the finer points of the Japanese language
select x.year y, x.month m, 100 - cast(x.posts as money)/cast(x1.posts as money)*100 perc from (select Year(CreationDate) year, Month(CreationDate) month, Count(PostTypeId) posts from Posts group by Year(CreationDate) , Month(CreationDate)) x join (select Year(CreationDate) year, Month(CreationDate) month, Count(PostTypeId) posts from Posts group by Year(CreationDate) , Month(CreationDate)) x1 on x.year =x1.year and x.month - x1.month = 1 and x.posts < x1.posts order by y,m;