COBOL: Subtract 1 year from current date

The below code snippet explains how to subtract one year from the current date.


....Working Storage....

01 MONTH-END-DD PIC X(24) VALUE '312831303130313130313031'.

01 TBL-MONTH-END REDEFINES MONTH-END-DD.

   03 TBL-MONTH-END-DAY OCCURS 12 TIMES.

   05 TBL-MONTH-END-DD PIC 9(02).

01 WS-DATE.

   02 YYYY PIC 9(4).

   02 MM PIC 99.

   02 DD PIC 99.

....Procedure Division....

MOVE my-date to WS-DATE

SUBTRACT 1 FROM YYYY

* Leap year Check

IF ( FUNCTION MOD (YYYY, 400) = 0) OR

   ( FUNCTION MOD (YYYY, 4) = 0 AND

     FUNCTION MOD (YYYY, 100) NOT = 0 )

     MOVE '29' TO MONTH-END-DD (3:2)

ELSE

     MOVE '28' TO MONTH-END-DD (3:2)

END-IF

IF DD > TBL-MONTH-END-DD (MM)

   MOVE TBL-MONTH-END-DD (MM) TO DD

END-IF