; with daterange as
(
	SELECT	frDate = convert(date, '2013-01-01'), toDate = convert(date, '2013-01-05')	union all
	SELECT	frDate = '2013-01-06', toDate = '2013-01-12'	union all
	SELECT	frDate = '2013-01-13', toDate = '2013-01-19'	union all
	SELECT	frDate = '2013-01-20', toDate = '2013-01-26'	union all
	SELECT	frDate = '2013-01-27', toDate = '2013-01-31'
)
SELECT 	count(distinct IAV) as IavCount,
	convert(varchar(10), frDate, 101) + ' - ' + convert(varchar(10), toDate, 101) as EachWeek
FROM 	IavInfo i
	INNER JOIN daterange d	ON	i.ScanDate BETWEEN frDate AND toDate
WHERE 	IAV 	<> 'N/A'
GROUP BY frDate, toDate
ORDER BY frDate