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declare @TestDate date;

set @TestDate = '20110401';

select @TestDate, DATEADD(mm,9,@TestDate), CAST(year(DATEADD(mm,9,@TestDate)) - 1 as VARCHAR) + '/' + RIGHT(CAST(year(DATEADD(mm,9,@TestDate)) as VARCHAR),2);

set @TestDate = '20120331';

select @TestDate, DATEADD(mm,9,@TestDate), CAST(year(DATEADD(mm,9,@TestDate)) - 1 as VARCHAR) + '/' + RIGHT(CAST(year(DATEADD(mm,9,@TestDate)) as VARCHAR),2);