Q&A for ebook publishers and readers
CREATE TABLE #Numbers ( Number DECIMAL(10,4), Variance DECIMAL(10,4) ); GO INSERT INTO #Numbers (Number) VALUES (23), (37), (45), (49), (56), (63), (63), (70), (72), (82); GO DECLARE @Mean DECIMAL(10,4); SET @Mean = (SELECT SUM (Number) / COUNT(Number) FROM #Numbers); -- @Mean is 100 UPDATE #Numbers SET Variance = POWER( (@Mean - Number), 2); DECLARE @StdVariance DECIMAL(10,4); SET @StdVariance = (SELECT SQRT( SUM((1.0 * Number - @Mean) * (1.0 * Number - @Mean)) / COUNT(Number) ) FROM #Numbers); SELECT @Mean AS [Mean], @StdVariance AS [Standard Variance], Avg(1.0 * Number) as [Avg], StDev(1.0 * Number) as [StdDev] from #Numbers