need help to improve this query....

Hi all,
I have the code below, which used for stock analysis base on the first in first out. As you can see if need a lot of help....the currently code is to slow, because of the while loop. I been struggling with this, and need some new input on how to rewrite these code. Any help to improve this thing is greatly appreciated.
DECLARE @OrderTable TABLE(
ROWID INT IDENTITY ( 1,1 ),
ID INT,
ACCT INT,
BUYDATE DATETIME,
SELLDATE DATETIME,
B_QTY INT,
B_COST MONEY,
S_QTY INT,
S_COST MONEY
)

DECLARE @t1 TABLE(
[ID] INTEGER IDENTITY ( 1,1 ),
ACCT INT,
XDATE DATETIME,
XCODE CHAR(1),
QTY INT,
COST MONEY
)

INSERT @t1 VALUES('100101','2003-10-2','B',100,50)
INSERT @t1 VALUES('100101','2003-10-2','B',200,45)
INSERT @t1 VALUES('100101','2003-10-1','B',300,35)
INSERT @t1 VALUES('100101','2003-10-1','S',400,55)
INSERT @t1 VALUES('100101','2003-10-2','S',200,20)
INSERT @t1 VALUES('100102','2003-10-2','B',500,12)
INSERT @t1 VALUES('100102','2003-10-3','S',800,13)
INSERT @t1 VALUES('100102','2003-10-3','B',500,11)
INSERT @t1 VALUES('100103','2003-10-4','B',100,12)
INSERT @t1 VALUES('100103','2003-10-5','B',200,12)
INSERT @t1 VALUES('100103','2003-10-6','S',500,15)

SELECT * FROM @T1

DECLARE @xCountMax INT,
@xCount INT,
@id_in INT,
@id_out INT,
@date1 DATETIME,
@date2 DATETIME,
@qtyin INT,
@qtyout INT,
@qtyin2 INT,
@qtyout2 INT,
@costin MONEY,
@costout MONEY,
@inClmid INT,
@outClmid INT,
@flagid INT,
@flagout INT,
@acct INT

SET @xCount = 1

IF OBJECT_ID('tempdb..#TMPCLMID','U') IS NOT NULL
DROP TABLE #TMPCLMID

SELECT IDENTITY(INT,1,1) AS ROWID,
ACCT
INTO #TMPCLMID
FROM @t1
GROUP BY ACCT

SET @xCount = 1

SET @xCountMax = (SELECT MAX(ROWID)
FROM #TMPCLMID)

WHILE @xCount <= @xCountMax
BEGIN

IF OBJECT_ID('tempdb..#buy','U') IS NOT NULL
DROP TABLE #BUY

IF OBJECT_ID('tempdb..#sell','U') IS NOT NULL
DROP TABLE #SELL

SELECT @ACCT = ACCT

FROM #TMPCLMID
WHERE ROWID = @xCount

SELECT IDENTITY(INT,0,1) AS ROWID,
ACCT,
XDATE,
XCODE,
QTY,
COST
INTO #BUY
FROM @t1
WHERE XCODE = 'B'
AND ACCT = @ACCT

SELECT IDENTITY(INT,0,1) AS ROWID,
ACCT,
XDATE,
XCODE,
QTY,
COST
INTO #SELL
FROM @t1
WHERE XCODE = 'S'
AND ACCT = @ACCT

SET @flagid = 0
SET @flagout = 0
SET @qtyout = 1
SET @qtyin = 1
SET @qtyout2 = 1
SET @qtyin2 = 1

WHILE (@qtyout <> 0
AND @qtyin <> 0)
BEGIN
IF @flagid = 0
BEGIN
SET @qtyout = 0

SET @qtyin = 0

SELECT @id_in = ROWID,
@date1 = XDATE,
@qtyin = QTY,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = 0

SELECT @id_out = ROWID,
@date2 = XDATE,
@qtyout = ISNULL(QTY,0),
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = 0

IF ISNULL(@qtyin,0) = 0
BEGIN
SET @id_in = @id_in + 1

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
SELECT @id_in = ROWID,
@date1 = XDATE,
@qtyin = QTY,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_in
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0
END
END

IF ISNULL(@qtyout,0) = 0
BEGIN
SET @id_out = @id_out + 1

IF EXISTS (SELECT 1
FROM #SELL
WHERE ROWID = @id_out)
SELECT @id_out = ROWID,
@date2 = XDATE,
@qtyout = QTY,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @id_out
ELSE
BEGIN
SET @qtyout = 0

SET @qtyout2 = 0
END
END

SET @flagid = @flagid + 1
END

IF (@qtyin >= @qtyout)
BEGIN
IF (@qtyout > 0)
BEGIN
INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyout,
@costin,
@date2,
@qtyout,
@costout,
@acct
END
ELSE
BEGIN
INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyin,
@costin,
NULL,
0,
0,
@acct

SET @id_in = @id_in + 1

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
SELECT @qtyin = QTY,
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_in
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0
END
END

SET @qtyin = @qtyin - @qtyout

SET @id_out = @id_out

SET @qtyout = @qtyout

SET @qtyin = @qtyin

SET @id_out = @id_out + 1

IF EXISTS (SELECT 1
FROM #SELL
WHERE ROWID = @id_out)
BEGIN
SELECT @qtyout = ISNULL(QTY,0),
@date2 = XDATE,
@qtyout = QTY,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @id_out

END
ELSE
BEGIN
SET @qtyout = 0

SET @qtyout2 = 0
END

SET @qtyout = @qtyout

IF (@qtyin < @qtyout)

BEGIN

INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyin,
@costin,
@date2,
@qtyin,
@costout,
@acct

SET @qtyout = ((@qtyout) - (@qtyin))
SET @id_in = @id_in
SET @id_in = @id_in + 1

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
SELECT @qtyin = ISNULL(QTY,0),
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_in
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0
END
END
ELSE
BEGIN
WHILE (@qtyin >= @qtyout)
BEGIN
SET @qtyout = @qtyout

IF @qtyout > 0
BEGIN
INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyout,
@costin,
@date2,
@qtyout,
@costout,
@acct
END

SET @qtyin = @qtyin - @qtyout

SET @id_out = @id_out + 1

IF @qtyin = 0
BEGIN

SET @id_in = @id_in + 1

SET @qtyout = @qtyout

IF EXISTS (SELECT 1
FROM #SELL
WHERE ROWID = @id_out)
SELECT @QTYOUT = QTY,
@date2 = XDATE,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @id_out
ELSE
BEGIN
SET @qtyout = 0

SET @qtyout2 = 0
END

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
SELECT @QTYIN = QTY,
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_IN
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0
END

BREAK
END

IF EXISTS (SELECT 1
FROM #SELL
WHERE ROWID = @id_out)
BEGIN
SELECT @QTYOUT = QTY,
@date2 = XDATE,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @id_out

SET @qtyin = @qtyin
END
ELSE
BEGIN
SET @qtyout = 0

SET @qtyin = ((@qtyin) - (@qtyout))

INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyin,
@costin,
NULL,
0,
0,
@acct

SET @id_in = @id_in

SET @id_in = @id_in + 1

SET @qtyout2 = 0

BREAK
END

END
END
END

ELSE
BEGIN

IF (@qtyin > 0)

BEGIN

INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyin,
@costin,
@date2,
@qtyin,
@costout,
@acct

SET @id_in = @id_in + 1

SET @qtyout = @qtyout - @qtyin

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
BEGIN
SELECT @QTYIN = QTY,
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_in

IF @qtyin > @qtyout2
SET @flagout = 0
END
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0
END

END
ELSE
BEGIN
INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
NULL,
0,
0,
@date2,
@qtyout,
@costout,
@acct

SET @id_in = @id_in + 1

IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
BEGIN
SELECT @QTYIN = QTY,
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @id_in

IF @qtyin > @qtyout2
SET @flagout = 0
END
ELSE
BEGIN
SET @qtyin = 0

SET @qtyin2 = 0

SET @ID_OUT = @ID_OUT + 1

SELECT @qtyout = QTY,
@date2 = XDATE,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @ID_OUT

END

END

END

IF @qtyout2 = 0

BEGIN
WHILE @qtyout2 <> 1
BEGIN
IF EXISTS (SELECT 1
FROM #BUY
WHERE ROWID = @id_in)
BEGIN
SELECT @qtyin = QTY,
@date1 = XDATE,
@costin = COST,
@acct = ACCT
FROM #BUY
WHERE ROWID = @ID_IN

SET @qtyin = @qtyin

INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
@date1,
@qtyin,
@costin,
NULL,
0,
0,
@acct

SET @ID_IN = @ID_IN + 1
END
ELSE
BEGIN
SET @qtyin2 = 0

SET @qtyin = 0

BREAK
END
END

END

IF @qtyin2 = 0
BEGIN

WHILE @qtyin2 <> 1
BEGIN
IF EXISTS (SELECT 1
FROM #SELL
WHERE ROWID = @id_out)
BEGIN
INSERT INTO @OrderTable
(ID,
BUYDATE,
B_QTY,
B_COST,
SELLDATE,
S_QTY,
S_COST,
ACCT)
SELECT @id_in,
NULL,
0,
0,
@date2,
@qtyout,
@costout,
@acct

SET @ID_OUT = @ID_OUT + 1

SELECT @qtyout = QTY,
@date2 = XDATE,
@costout = COST,
@acct = ACCT
FROM #SELL
WHERE ROWID = @ID_OUT
END
ELSE
BEGIN
SET @qtyout2 = 0

SET @qtyout = 0

BREAK
END
END
END
END

SET @xCount = @xCount + 1

END

SELECT rowid,acct,buydate,selldate,b_qty,b_cost,s_qty,s_cost
FROM @OrderTable
ORDER BY ACCT

Hi Satya,
the index is on the rowid. I beleived the while loop is the one causing problem. If individual account is processing, it took around 2 seconds, but when group with other accounts, the while loop is taking to much time.
thanks