DECLARE @gt TABLE
(
    value DECIMAL(23, 8),
    item NVARCHAR(50),
    qty DECIMAL(23, 8)
);
INSERT INTO @gt


--- giá trị( ĐẦU KÌ   + nhập trong - xuất trong kì) / số lượng

SELECT SUM(a.VALUE),
       a.item, --, SUM(TT)
       SUM(qty)
FROM
(
    SELECT CASE
               WHEN SUM(qty) <> 0 THEN
        (SUM(ISNULL(TON, 0) + ISNULL(N, 0) + ISNULL(X, 0)) / SUM(qty)) * SUM(C) -- * -- * SUM(C)
               ELSE
                   0
           END VALUE, --AS decimal(28,7),
           A.item,
           SUM(qty) qty
    --,(SUM(TON + N + X) / SUM(qty)) 	  TT
    FROM
    ( -- XUẤT
        SELECT 0.0 C,
               0.0 N,
               (ISNULL(A.value, 0)) X,
               0.0 TON,
               ISNULL(qty, 0) qty,
               A.item
        FROM
        (
            SELECT m.site_ref AS site,
                   (m.item) item,
                   SUM(ISNULL(m.qty, 0)) qty,
                   SUM(ISNULL(qty, 0) * ISNULL(cost, 0)) value
            FROM ERP.SyteLine_Apps.dbo.matltran_mst m WITH (NOLOCK)
                --JOIN ERP.SyteLine_Apps.dbo.item_mst i WITH (NOLOCK)
                    --ON i.item = m.item
                    --   AND m.site_ref = i.site_ref
            WHERE MONTH(m.trans_date) = MONTH(('2019-08-01'))
                  AND YEAR(m.trans_date) = 2019
                  --AND i.product_code = 'pfg'
                  -- AND LEFT(m.item, 2) IN ( 'AA', 'AC', 'AN' )
                  AND m.whse = 'BTL'
                  AND m.site_ref = 'PVD'
                  AND m.loc IS NOT NULL
                  AND m.qty < 0
				      AND EXISTS ( SELECT 1
                                     FROM   ERP.SyteLine_Apps.dbo.item_mst
                                     WHERE  item = m.item
                                            AND product_code = 'PFG' )
            --AND (m.item) = 'AA184095C060N1100'
            GROUP BY (m.item),
                     m.site_ref
        ) A
        WHERE A.qty <> 0
        UNION ALL
        SELECT 0.0 C,
               (ISNULL(A.value, 0)) N,
               0.0 X,
               0 TON,
               ISNULL(A.qty, 0) qty,
               A.item
        FROM
        ( -- NHẬP
            SELECT m.site_ref AS site,
                   (m.item) item,
                   SUM(ISNULL(m.qty, 0)) qty,
                   SUM(ISNULL(qty, 0) * ISNULL(cost, 0)) value
            FROM ERP.SyteLine_Apps.dbo.matltran_mst m
                --JOIN ERP.SyteLine_Apps.dbo.item_mst i WITH (NOLOCK)
                --    ON i.item = m.item
                --       AND m.site_ref = i.site_ref
            WHERE MONTH(m.trans_date) = MONTH(('2019-08-01'))
                  AND YEAR(m.trans_date) = 2019
                  --AND i.product_code = 'pfg'
                  AND m.whse = 'BTL'
                  AND m.site_ref = 'PVD'
                  AND m.loc IS NOT NULL
                  AND m.qty > 0
				      AND EXISTS ( SELECT 1
                                     FROM   ERP.SyteLine_Apps.dbo.item_mst
                                     WHERE  item = m.item
                                            AND product_code = 'PFG' )
            --AND (m.item) = 'AA184095C060N1100'
            GROUP BY (m.item),
                     m.site_ref
        ) A
        WHERE A.qty <> 0
        UNION ALL
        SELECT 0 C,
               0 N,
               0 X,
               (ISNULL(A.value, 0)) TON,
               ISNULL(A.qty, 0) qty,
               A.item
        FROM
        ( -- ĐẦU KÌ
            SELECT m.site_ref AS site,
                   (m.item) item,
                   SUM(ISNULL(m.qty, 0)) qty,
                   SUM(ISNULL(qty, 0) * ISNULL(cost, 0)) value
            FROM ERP.SyteLine_Apps.dbo.matltran_mst m
                --JOIN ERP.SyteLine_Apps.dbo.item_mst i WITH (NOLOCK)
                --    ON i.item = m.item
                --       AND m.site_ref = i.site_ref
            WHERE CAST(m.trans_date AS DATE) < ('2019-08-01')
                  --AND i.product_code = 'pfg'
                  AND m.whse = 'BTL'
                  AND m.site_ref = 'PVD'
                  AND m.loc IS NOT NULL
                  AND m.qty <> 0
				      AND EXISTS ( SELECT 1
                                     FROM   ERP.SyteLine_Apps.dbo.item_mst
                                     WHERE  item = m.item
                                            AND product_code = 'PFG' )
            --AND (m.item) = 'AA184095C060N1100'
            GROUP BY (m.item),
                     m.site_ref
        ) A
        WHERE A.qty <> 0
        UNION ALL
        SELECT SUM(ISNULL(qty, 0)) C,
               0 N,
               0 X,
               0 TON,
               0 qty,
               A.item
        FROM
        (
            SELECT m.site_ref AS site,
                   (m.item) item,
                   SUM(ISNULL(m.qty, 0)) qty,
                   SUM(ISNULL(qty, 0) * ISNULL(cost, 0)) value
            FROM ERP.SyteLine_Apps.dbo.matltran_mst m
                --JOIN ERP.SyteLine_Apps.dbo.item_mst i WITH (NOLOCK)
                --    ON i.item = m.item
                --       AND m.site_ref = i.site_ref
            WHERE CAST(m.trans_date AS DATE) <= ('2019-08-31')
                  --AND i.product_code = 'pfg'
                  AND m.whse = 'BTL'
                  AND m.site_ref = 'PVD'
                  AND m.loc IS NOT NULL
                  AND m.qty <> 0
				      AND EXISTS ( SELECT 1
                                     FROM   ERP.SyteLine_Apps.dbo.item_mst
                                     WHERE  item = m.item
                                            AND product_code = 'PFG' )
            --AND    M.item ='AA184095C060N1100'
            GROUP BY (m.item),
                     m.site_ref
        ) A
        WHERE A.qty <> 0
        GROUP BY A.item
    ) A
    --  WHERE value <>0

    GROUP BY A.item
) a
GROUP BY a.item;

--PRINT @gt
--SET  @gt= (@gt/2329) *   2329
SELECT *
FROM @gt;
-- WHERE a.item='AA151028B050N1200'
--WHERE a.VALUE <> 0;