SELECT [AgeByGroup] [AgeGroup], COUNT([AgeByGroup])
FROM (SELECT
		CASE
			WHEN [Age] BETWEEN 0 AND 10 THEN '[0-10]'
			WHEN [Age] BETWEEN 11 AND 20 THEN '[11-20]'
			WHEN [Age] BETWEEN 21 AND 30 THEN '[21-30]'
			WHEN [Age] BETWEEN 31 AND 40 THEN '[31-40]'
			WHEN [Age] BETWEEN 41 AND 50 THEN '[41-50]'
			WHEN [Age] BETWEEN 51 AND 60 THEN '[51-60]'
			ELSE '[61+]'
		END AS [AgeByGroup]
		FROM [WizzardDeposits]) [AgeByGroupTable]
GROUP BY [AgeByGroup]