no of weeks according to company code?

Dear Gurus,

                 Hi everyone. I need a FM which will return me the no of weeks according to company code. My planning book data view returning me 53 weeks an year where as the FM on the SAP APO side returning me 52 Weeks in the same year. Can someone please guide me I have been creating dynamic alv according to planning book data views. I have been using the FM which return me 52 weeks but in plnning book data view it is 53 weeks.

in /n/sapapo/sdp94.

Or is there any Method of class or FM which will return me the header of Data view of any Planning book.

CALL FUNCTION '/SAPAPO/PERIOD_GET_FOR_DATE'

*              EXPORTING

*                I_DATE      = I_DATE

*                I_PERKZ     = 'W'

*                I_PERIV     = 'AL'

*              IMPORTING

*                E_PERID     = E_PERID

*              EXCEPTIONS

*                WRONG_PERKZ = 1

*                WRONG_DATE  = 2

*                WRONG_PERIV = 3

*                OTHERS      = 4.

*            IF SY-SUBRC <> 0.

*              MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO

*                      WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.