Calculate Easter Date

SET QUOTED_IDENTIFIER OFF 
GO
SET ANSI_NULLS OFF 
GO

CREATE FUNCTION dbo.fcn_FindEasterSunday(@inYear int)
RETURNS datetime
AS
BEGIN
    DECLARE @dtNow datetime
    DECLARE @inCurDay int
    DECLARE @inCurMonth int
    DECLARE @inCurYear int
    DECLARE @inCurCent int
    DECLARE @inYear19 int
    DECLARE @inYearTmp int
    DECLARE @inTemp2 int
    DECLARE @inTemp3 int
    DECLARE @inTemp4 int
    DECLARE @inEastDay int
    DECLARE @inEastMonth int
    DECLARE @dtEasterSunday datetime

    SET @dtNow = CONVERT(datetime,CAST(@inYear as char(4))+'-01-01')

    SET @inCurDay=DAY(@dtNow)
    SET @inCurMonth=MONTH(@dtNow)
    SET @inCurYear=YEAR(@dtNow)
    SET @inCurCent=FLOOR(@inCurYear/100)

    SET @inYear19=@inCurYear%19

    SET @inYearTmp=FLOOR((@inCurCent-17)/25)
    SET @inTemp2=(@inCurCent-FLOOR(@inCurCent/4)-FLOOR((@inCurCent-@inYearTmp)/3)+(19*@inYear19)+15)%30
    SET @inTemp2=@inTemp2-FLOOR(@inTemp2/28)*(1 - FLOOR(@inTemp2/28)*FLOOR(29/(@inTemp2+1))*FLOOR((21-@inYear19)/11))

    SET @inTemp3 = (@inCurYear+FLOOR(@inCurYear/4)+@inTemp2+2-@inCurCent+FLOOR(@inCurCent/4))%7
    SET @inTemp4 = @inTemp2-@inTemp3

    SET @inEastMonth = 3+FLOOR((@inTemp4+40)/44)
    SET @inEastDay = @inTemp4+28-31*FLOOR(@inEastMonth/4)
    SET @inEastMonth = @inEastMonth - 1

    SET @dtEasterSunday = CONVERT(datetime,CAST(@inCurYear as varchar(4))+'-'+RIGHT(CAST('00' as varchar(2))+CAST(@inEastMonth+1 as varchar(2)),2)+'-'+RIGHT(CAST('00' as varchar(2))+CAST(@inEastDay as varchar(2)),2)+' 00:00:00')
    RETURN @dtEasterSunday
END
GO
SET QUOTED_IDENTIFIER OFF 
GO
SET ANSI_NULLS ON 
GO