WorkingDaysDiff complementary UDF for DATEDIFF

/**************************************************//* Pass in a datetime and it will return the date *//* portion with the time set to 00:00:00          *//**************************************************/CREATE FUNCTION fn_Midnight (@CheckDate datetime)  
RETURNS datetime AS  
BEGIN 

-- Strip out the date and rebuild, kind of a bionic date - we can rebuild it!
Declare @NewDateTime datetime

Set @NewDateTime = DateAdd(yyyy, Year(@CheckDate) - 1900, 0)
Set @NewDateTime = DateAdd(mm, Month(@CheckDate) - 1, @NewDateTime)
Set @NewDateTime = DateAdd(dd, Day(@CheckDate) - 1, @NewDateTime)

Return @NewDateTime

END


/**************************************************//* Pass in an offset of days                      *//* -1 = yesterday, 1 is tomorrow etc              *//* and it will return the date that number of     *//* working days before or after the date specified*//* by the second parameter                        *//**************************************************/CREATE FUNCTION fn_WorkingDaysDiff(@Offset int, @TheDate datetime)
RETURNS DATETIME
AS
BEGIN
Declare @ReturnDate datetime

-- Drop the date to midnight
Set @TheDate = dbo.fn_Midnight(@TheDate)

If @Offset = 0
Begin
Set @ReturnDate = @TheDate
End
Else If @Offset < 0
Begin
If (DatePart(dw, @TheDate)-1) > Abs(@Offset)
Begin
Set @ReturnDate = DateAdd(d, @Offset, @TheDate)
End
Else
Begin
-- Correct for sundays
If DatePart(dw, @TheDate) = 1 Set @Offset = @Offset + 1
Set @ReturnDate = DateAdd(d, @OffSet + 2 * Cast((DatePart(dw, @TheDate) + @OffSet - 1)/5-1 as integer), @TheDate)
End
End
Else If @Offset > -1
Begin
If (DatePart(dw, @TheDate) + @Offset) < 7
Begin
Set @ReturnDate = DateAdd(d, @Offset, @TheDate)
End
Else
Begin
-- Correct for Saturday error
If DatePart(dw, @TheDate) = 7 Set @Offset = @Offset - 1
Set @ReturnDate = DateAdd(d, Cast((DatePart(dw, @TheDate) + @Offset - 2) /5 as integer)*2 + @Offset, @TheDate)
End
End

Return @ReturnDate

END