Q&A for those using, extending or developing Emacs
select convert(float,datepart(year, P.CreationDate)+datepart(month, P.CreationDate)/100), count(*) n from Posts P join PostTags PT on P.Id = PT.PostId join Tags T on PT.TagId = T.Id where T.TagName = 'wpf' group by datepart(year, P.CreationDate)+datepart(month, P.CreationDate)/100