Performance Issue while fetching from COSP table

Hi,

Please helip in improving the performance of the below SELECT Query.This currently uses the LEFT OUTER JOIN, which is time consuming. Please let me know if there are any alternatives for this.

SELECT gjahr p~objnr f~bukrs auart autyp versn

SUM( wog001 )
SUM( wog002 )
SUM( wog003 )
SUM( wog004 )
SUM( wog005 )
SUM( wog006 )
SUM( wog007 )
SUM( wog008 )
SUM( wog009 )
SUM( wog010 )
SUM( wog011 )
SUM( wog012 )
SUM( wog013 )
SUM( wog014 )
SUM( wog015 )
SUM( wog016 )
APPENDING TABLE gt_coxx
FROM cosp AS p
LEFT OUTER JOIN aufk AS f
ON p~objnr = f~objnr
WHERE lednr = '00'
AND p~objnr IN p_objnr
AND gjahr EQ p_gjahr
AND p~versn EQ p_versn
AND p~wrttp EQ p_wrttp
AND p~vrgng NE 'COIN'
GROUP BY gjahr p~objnr f~bukrs auart autyp versn.