Now I do not really know why you are doing these calculations, but you could add one more item to the code to give you an overall view of the length of the contents of that table column:

CREATE TABLE #T(tmessage VARCHAR(200))

INSERT INTO #T

SELECT 'Short' UNION ALL

SELECT 'Longer' UNION ALL

SELECT 'Even a longer message' UNION ALL

SELECT 'A realy realy realy extra long message truly really long'

select SUM(200 -Len(tmessage)) AS WASTED,AVG(200 -Len(tmessage)) AS 'Average Wasted',

MIN(200 -Len(tmessage)) AS 'Minimum Wasted'

FROM #T

DROP TABLE #T

WASTEDAverage WastedMinimum Wasted

. . 712 . . . . . 178 . . . . . . .144

But if you are considering altering the size of columns in a existing table, the above could be more useful.