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SELECT YEAR(u.CreationDate) AS u_year , COUNT(1) AS u_count , SUM(p.p_count) AS p_count , CONVERT(decimal(6,3),CONVERT(decimal,SUM(p.p_count))/CONVERT(decimal,COUNT(1))) AS ppu_avg , MAX(p.p_count) AS p_count_max , MIN(p.p_count) AS p_count_min FROM Users u INNER JOIN ( SELECT p.OwnerUserId , YEAR(p.CreationDate) AS p_year , COUNT(1) AS p_count FROM Posts p WHERE p.PostTypeId = 1 GROUP BY p.OwnerUserId , YEAR(p.CreationDate) ) p ON p.OwnerUserId = u.Id AND p.p_year = YEAR(u.CreationDate) GROUP BY YEAR(u.CreationDate) ORDER BY u_year