COBOL BLANK WHEN ZERO Clause

• BLANK WHEN ZERO clause makes a variable display the SPACES when its value is ZERO.
• It should code with a numeric or numeric-edited variable.
• This clause is used only on elementary variables and is coded anywhere in Area B but not in Area A.

Syntax -

Rules to Remember -

• Elementary variables should be declared USAGE as DISPLAY.
• Numeric-edited items declared with BLANK WHEN ZERO shouldn't be used in arithmetic operations (ADD, SUBTRACT, MULTIPLY, DIVIDE, and COMPUTE).
• BLANK WHEN ZERO clause should not code with level-66 and level-88.
• BLANK WHEN ZERO clause should not code with the variables declared with S or *.

Practical Example -

Scenario - Explaining how the BLANK WHEN ZERO is used in COBOL programming.

Code -

----+----1----+----2----+----3----+----4----+----5----+
       ...
	   DATA DIVISION.
       WORKING-STORAGE SECTION. 
       01 WS-VAR. 
          05 WS-NED-VAR    PIC ZZ,ZZ9.9(2).
	  * Declaring a variable with BLANK WHEN ZERO
          05 WS-BWZ-VAR    PIC ZZ,ZZ9.9(2) BLANK WHEN ZEROES.
       ...
       PROCEDURE DIVISION. 

           MOVE ZEROES         TO WS-NED-VAR 
                                  WS-BWZ-VAR.
           DISPLAY "WS-NED-VAR: " WS-NED-VAR. 
           DISPLAY "WS-BWZ-VAR: " WS-BWZ-VAR.
           DISPLAY " ".
           ...

Output -

WS-NED-VAR:      0.00  
WS-BWZ-VAR: