instruction: Percent DND questions by month.
response: SELECT DATEADD(month, DATEDIFF(month, 0, CreationDate), 0) AS Mnth, (SUM(CASE WHEN Tags LIKE '%dnd%' OR Tags LIKE '%dungeons-and-dragons%' OR Tags LIKE '%pathfinder%' THEN 1 ELSE 0 END) * 100.00) / COUNT(*) AS PercentDND FROM Posts WHERE PostTypeId = 1 GROUP BY DATEADD(month, DATEDIFF(month, 0, CreationDate), 0) ORDER BY DATEADD(month, DATEDIFF(month, 0, CreationDate), 0)