Q&A for professional and enthusiast programmers
SELECT DATEPART(Year, Users.CreationDate), COUNT(*) FROM Users WHERE EXISTS(SELECT 1 FROM Posts WHERE Posts.OwnerUserId = Users.Id AND Posts.PostTypeId = 2 -- answer AND Posts.Score > 0 AND DATEDIFF(Month, Users.CreationDate, Posts.CreationDate) < 3) GROUP BY DATEPART(Year, Users.CreationDate) ORDER BY DATEPART(Year, Users.CreationDate)