SELECT ANO, MES,SUM(VALORFAC) AS VALORFAC FROM
(SELECT    YEAR(TR.FECHA) AS ANO,MONTH(TR.FECHA) AS MES,
                  CASE WHEN DCTOMAE IN ('FA','FR')
                  THEN SUM(MV.VALORUNIT * MV.CANTIDAD - MV.VALORUNIT * MV.CANTIDAD * MV.DESCUENTO / 100 )
                  WHEN DCTOMAE='NC'
                  THEN SUM((MV.VALORUNIT * MV.CANTIDAD - MV.VALORUNIT * MV.CANTIDAD * MV.DESCUENTO / 100 )*-1)
                  END AS VALORFAC
FROM        TRADE AS TR INNER JOIN MVTRADE AS MV ON TR.NRODCTO = MV.NRODCTO
                  AND TR.TIPODCTO = MV.TIPODCTO AND TR.ORIGEN = MV.ORIGEN INNER JOIN TIPODCTO AS TD
                  ON TD.TIPODCTO = TR.TIPODCTO AND TD.TIPODCTO = MV.TIPODCTO AND TD.ORIGEN = MV.ORIGEN AND
            TD.ORIGEN = TR.ORIGEN INNER JOIN  MTMERCIA AS ME ON ME.CODIGO = MV.PRODUCTO
                  INNER JOIN MTLINEA AS LI ON LI.CODLINEA = ME.CODLINEA
WHERE     (TR.ORIGEN = 'FAC') AND (TD.DCTOMAE  IN ('FA', 'FR','NC'))
                  AND (DATEDIFF(MM, TR.FECHA, '2009-12-31') BETWEEN '1' AND '6')
                  /*AND ME.CODLINEA IN ('REPIN','REPAN')*/
                  GROUP BY YEAR(TR.FECHA) ,MONTH(TR.FECHA),DCTOMAE
) AS VTAS
                  GROUP BY ANO,MES
                  ORDER BY ANO,MES