Elapsed time between dates

/*
Returns the number of years, months and days between @startdate and @enddate in a table format
USAGE: "Select * From dbo.udfElapsedDate('09/11/2001','07/04/2004)"
*/
CREATE FUNCTION udfElapsedDate (
@startdate SMALLDATETIME,
@enddate SMALLDATETIME
)  
RETURNS @retElapsed TABLE (Years SMALLINT, Months TINYINT, Days TINYINT) AS
BEGIN 
DECLARE @smonth TINYINT, @sday TINYINT, @syear SMALLINT
DECLARE @emonth TINYINT, @eday TINYINT, @eyear SMALLINT
DECLARE @months TINYINT, @days TINYINT, @years SMALLINT
DECLARE @tdate SMALLDATETIME
SET @smonth = MONTH(@startdate)
SET @sday = DAY(@startdate)
SET @syear = YEAR(@startdate)
SET @emonth = MONTH(@enddate)
SET @eday = DAY(@enddate)
SET @eyear = YEAR(@enddate)
SET @years = @eyear - @syear
SET @months = 0
SET @days = 0
IF (@emonth >= @smonth)
SET @months = @emonth - @smonth
ELSE
BEGIN
SET @years = @years - 1
SET @months = @emonth + 12 - @smonth
END
IF (@eday >= @sday)
SET @days = @eday - @sday
ELSE
BEGIN
IF (@months > 0)
SET @months = @months - 1
ELSE
BEGIN
SET @years = @years - 1
SET @months = @months + 11
END
SET @tdate = DATEADD(yy,@years,@startdate)
SET @tdate = DATEADD(m,@months,@tdate)
SET @days = DATEDIFF(d,@tdate,@enddate)
END
INSERT @retElapsed SELECT @years, @months, @days
RETURN
END

/*
Returns the number of years, months and days between @startdate and @enddate but requires 3 calls, 1 for each of Y,M,D
USAGE: select dbo.udfElapsedDatePart ('09/11/2001','07/04/2004','D')
*/
CREATE FUNCTION udfElapsedDatePart (
@startdate SMALLDATETIME,
@enddate SMALLDATETIME,
@period CHAR(1)
)
RETURNS INT AS
BEGIN 
DECLARE @smonth TINYINT, @sday TINYINT, @syear SMALLINT
DECLARE @emonth TINYINT, @eday TINYINT, @eyear SMALLINT
DECLARE @months TINYINT, @days TINYINT, @years SMALLINT
DECLARE @tdate SMALLDATETIME, @ret INT
SET @smonth = MONTH(@startdate)
SET @sday = DAY(@startdate)
SET @syear = YEAR(@startdate)
SET @emonth = MONTH(@enddate)
SET @eday = DAY(@enddate)
SET @eyear = YEAR(@enddate)
SET @years = @eyear - @syear
SET @months = 0
SET @days = 0
IF (@emonth >= @smonth)
SET @months = @emonth - @smonth
ELSE
BEGIN
SET @years = @years - 1
SET @months = @emonth + 12 - @smonth
END
IF (@eday >= @sday)
SET @days = @eday - @sday
ELSE
BEGIN
IF (@months > 0)
SET @months = @months - 1
ELSE
BEGIN
SET @years = @years - 1
SET @months = @months + 11
END
SET @tdate = DATEADD(yy,@years,@startdate)
SET @tdate = DATEADD(m,@months,@tdate)
SET @days = DATEDIFF(d,@tdate,@enddate)
END
IF @period = 'Y'
SET @ret = @years
IF @period = 'M'
SET @ret = @months
IF @period = 'D'
SET @ret = @days
RETURN @ret
END