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COBOL Standards

COBOL standards define the official specifications for the COBOL programming language, ensuring consistency, portability, and compatibility across different systems and implementations. Understanding these standards is crucial for writing maintainable, portable COBOL code that can run on various platforms and be easily maintained by different developers.

Understanding COBOL Standards

COBOL standards are developed by international organizations like ISO and ANSI to provide a common specification that all COBOL implementations should follow. These standards evolve over time, adding new features while maintaining backward compatibility. Following standards ensures that your code will work across different systems and can be maintained by any COBOL programmer familiar with the standard.

Evolution of COBOL Standards

1. COBOL-60 (Original Standard)

The original COBOL standard was developed in 1960 by the Conference on Data Systems Languages (CODASYL). This established the basic structure and syntax that all subsequent standards have built upon. While primitive by today's standards, it introduced the fundamental concepts that make COBOL readable and business-oriented.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. ORIGINAL-COBOL-EXAMPLE.
       *> This demonstrates the original COBOL-60 structure
       *> Note the basic division structure that remains today
       
       ENVIRONMENT DIVISION.
       CONFIGURATION SECTION.
       SOURCE-COMPUTER. IBM-360.
       OBJECT-COMPUTER. IBM-360.
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 CUSTOMER-RECORD.
           05 CUSTOMER-NUMBER    PIC 9(6).
           05 CUSTOMER-NAME      PIC X(30).
           05 CUSTOMER-BALANCE   PIC 9(8)V99.
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           MOVE 123456 TO CUSTOMER-NUMBER
           MOVE 'JOHN SMITH' TO CUSTOMER-NAME
           MOVE 1500.75 TO CUSTOMER-BALANCE
           DISPLAY 'CUSTOMER: ' CUSTOMER-NUMBER ' ' CUSTOMER-NAME
           DISPLAY 'BALANCE: ' CUSTOMER-BALANCE
           STOP RUN.

The original COBOL-60 standard established the four-division structure (IDENTIFICATION, ENVIRONMENT, DATA, PROCEDURE) that remains fundamental to COBOL today. It introduced the concept of level numbers for data hierarchy, picture clauses for data formatting, and the basic control structures. While limited compared to modern standards, it provided a solid foundation for business programming.

2. COBOL-74 (Enhanced Standard)

The 1974 ANSI standard added significant improvements including better file handling, enhanced arithmetic operations, and improved debugging capabilities. This standard made COBOL more robust and suitable for larger, more complex business applications.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. COBOL74-EXAMPLE.
       *> COBOL-74 introduced enhanced file handling and debugging
       
       ENVIRONMENT DIVISION.
       INPUT-OUTPUT SECTION.
       FILE-CONTROL.
           SELECT CUSTOMER-FILE ASSIGN TO 'CUSTOMER.DAT'
               ORGANIZATION IS SEQUENTIAL
               ACCESS MODE IS SEQUENTIAL
               FILE STATUS IS FILE-STATUS.
       
       DATA DIVISION.
       FILE SECTION.
       FD CUSTOMER-FILE.
       01 CUSTOMER-RECORD.
           05 CUSTOMER-NUMBER    PIC 9(6).
           05 CUSTOMER-NAME      PIC X(30).
           05 CUSTOMER-BALANCE   PIC 9(8)V99.
       
       WORKING-STORAGE SECTION.
       01 FILE-STATUS           PIC XX.
           88 FILE-OK           VALUE '00'.
           88 FILE-EOF          VALUE '10'.
           88 FILE-ERROR        VALUE '99'.
       01 RECORD-COUNT          PIC 9(6) VALUE 0.
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           OPEN INPUT CUSTOMER-FILE
           IF NOT FILE-OK
               DISPLAY 'ERROR OPENING FILE: ' FILE-STATUS
               STOP RUN
           END-IF
           
           PERFORM READ-CUSTOMER-RECORDS UNTIL FILE-EOF
           
           CLOSE CUSTOMER-FILE
           DISPLAY 'TOTAL RECORDS PROCESSED: ' RECORD-COUNT
           STOP RUN.
       
       READ-CUSTOMER-RECORDS.
           READ CUSTOMER-FILE
               AT END SET FILE-EOF TO TRUE
               NOT AT END
                   ADD 1 TO RECORD-COUNT
                   DISPLAY 'CUSTOMER: ' CUSTOMER-NUMBER ' ' CUSTOMER-NAME
           END-READ.

COBOL-74 introduced the FILE-CONTROL paragraph for better file management, FILE STATUS clauses for error handling, and improved READ statement syntax with AT END and NOT AT END clauses. These enhancements made file processing more reliable and easier to debug, which was crucial for business applications that heavily rely on data files.

3. COBOL-85 (Structured Programming)

The 1985 ANSI standard was a major milestone that introduced structured programming features to COBOL. This included END-IF, END-PERFORM, and other scope terminators that made COBOL code more readable and maintainable. It also added improved control structures and better error handling.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. COBOL85-EXAMPLE.
       *> COBOL-85 introduced structured programming features
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 CUSTOMER-DATA.
           05 CUSTOMER-NUMBER    PIC 9(6).
           05 CUSTOMER-NAME      PIC X(30).
           05 CUSTOMER-BALANCE   PIC 9(8)V99.
           05 ACCOUNT-TYPE       PIC X(1).
               88 CHECKING       VALUE 'C'.
               88 SAVINGS        VALUE 'S'.
       
       01 PROCESSING-CONTROLS.
           05 RECORD-COUNT      PIC 9(6) VALUE 0.
           05 TOTAL-BALANCE     PIC 9(12)V99 VALUE 0.
           05 AVERAGE-BALANCE   PIC 9(8)V99 VALUE 0.
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           PERFORM INITIALIZE-PROCESSING
           PERFORM PROCESS-CUSTOMER-DATA
           PERFORM CALCULATE-STATISTICS
           PERFORM DISPLAY-RESULTS
           STOP RUN.
       
       INITIALIZE-PROCESSING.
           MOVE 0 TO RECORD-COUNT
           MOVE 0 TO TOTAL-BALANCE
           DISPLAY 'Starting customer data processing'.
       
       PROCESS-CUSTOMER-DATA.
           PERFORM VARYING CUSTOMER-NUMBER FROM 100001 BY 1
               UNTIL CUSTOMER-NUMBER > 100010
               PERFORM PROCESS-SINGLE-CUSTOMER
           END-PERFORM.
       
       PROCESS-SINGLE-CUSTOMER.
           ADD 1 TO RECORD-COUNT
           
           *> Simulate different account types and balances
           IF CUSTOMER-NUMBER MOD 2 = 0
               SET CHECKING TO TRUE
               MOVE 2500.00 TO CUSTOMER-BALANCE
           ELSE
               SET SAVINGS TO TRUE
               MOVE 5000.00 TO CUSTOMER-BALANCE
           END-IF
           
           ADD CUSTOMER-BALANCE TO TOTAL-BALANCE
           
           DISPLAY 'Customer ' CUSTOMER-NUMBER ' processed'.
       
       CALCULATE-STATISTICS.
           IF RECORD-COUNT > 0
               COMPUTE AVERAGE-BALANCE = TOTAL-BALANCE / RECORD-COUNT
           ELSE
               MOVE 0 TO AVERAGE-BALANCE
           END-IF.
       
       DISPLAY-RESULTS.
           DISPLAY 'Processing complete'
           DISPLAY 'Records processed: ' RECORD-COUNT
           DISPLAY 'Total balance: ' TOTAL-BALANCE
           DISPLAY 'Average balance: ' AVERAGE-BALANCE.

COBOL-85 introduced scope terminators (END-IF, END-PERFORM) that make code much more readable and maintainable. The PERFORM VARYING statement provides structured loops, and the improved IF-THEN-ELSE structure eliminates the need for GO TO statements in most cases. These features made COBOL code more structured and easier to understand, following modern programming principles.

Modern COBOL Standards

1. COBOL-2002 (Object-Oriented Features)

The 2002 ISO standard brought object-oriented programming capabilities to COBOL, including classes, objects, inheritance, and polymorphism. This was a major evolution that allowed COBOL to compete with modern programming languages while maintaining its business-oriented focus.

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       IDENTIFICATION DIVISION.
       CLASS-ID. BANK-ACCOUNT.
       *> COBOL-2002 introduced object-oriented programming
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 ACCOUNT-NUMBER       PIC 9(10).
       01 ACCOUNT-HOLDER       PIC X(50).
       01 ACCOUNT-BALANCE       PIC 9(10)V99.
       01 ACCOUNT-TYPE          PIC X(10).
       
       PROCEDURE DIVISION.
       
       METHOD-ID. INITIALIZE-ACCOUNT.
       DATA DIVISION.
       LINKAGE SECTION.
       01 ACCOUNT-NUM          PIC 9(10).
       01 HOLDER-NAME          PIC X(50).
       01 INITIAL-BALANCE      PIC 9(10)V99.
       
       PROCEDURE DIVISION USING ACCOUNT-NUM
                                HOLDER-NAME
                                INITIAL-BALANCE.
           MOVE ACCOUNT-NUM TO ACCOUNT-NUMBER
           MOVE HOLDER-NAME TO ACCOUNT-HOLDER
           MOVE INITIAL-BALANCE TO ACCOUNT-BALANCE
           MOVE 'CHECKING' TO ACCOUNT-TYPE
           
       END METHOD INITIALIZE-ACCOUNT.
       
       METHOD-ID. DEPOSIT.
       DATA DIVISION.
       LINKAGE SECTION.
       01 DEPOSIT-AMOUNT       PIC 9(8)V99.
       01 TRANSACTION-SUCCESS  PIC X(1).
           88 SUCCESS          VALUE 'Y'.
           88 FAILURE          VALUE 'N'.
       
       PROCEDURE DIVISION USING DEPOSIT-AMOUNT
                       RETURNING TRANSACTION-SUCCESS.
           IF DEPOSIT-AMOUNT > 0
               ADD DEPOSIT-AMOUNT TO ACCOUNT-BALANCE
               SET SUCCESS TO TRUE
           ELSE
               SET FAILURE TO TRUE
           END-IF
           
       END METHOD DEPOSIT.
       
       METHOD-ID. GET-BALANCE.
       DATA DIVISION.
       LINKAGE SECTION.
       01 CURRENT-BALANCE      PIC 9(10)V99.
       
       PROCEDURE DIVISION RETURNING CURRENT-BALANCE.
           MOVE ACCOUNT-BALANCE TO CURRENT-BALANCE
           
       END METHOD GET-BALANCE.
       
       END CLASS BANK-ACCOUNT.

COBOL-2002 introduced the CLASS-ID statement for defining classes, METHOD-ID for defining methods, and the INVOKE statement for calling methods on objects. This brought modern object-oriented programming concepts to COBOL while maintaining the language's readability and business focus. The standard also included improved string handling and enhanced arithmetic operations.

2. COBOL-2014 (Latest Standard)

The 2014 ISO standard is the most recent and includes enhanced object-oriented features, improved Unicode support, better integration capabilities, and modern programming practices. It represents the current state of the COBOL language and provides the foundation for future development.

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       IDENTIFICATION DIVISION.
       CLASS-ID. MODERN-BANK-ACCOUNT.
       *> COBOL-2014 includes enhanced OOP features and modern constructs
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 ACCOUNT-DATA.
           05 ACCOUNT-NUMBER       PIC 9(10).
           05 ACCOUNT-HOLDER       PIC X(50).
           05 ACCOUNT-BALANCE       PIC 9(10)V99.
           05 ACCOUNT-TYPE          PIC X(10).
           05 CREATION-DATE         PIC X(10).
           05 LAST-TRANSACTION-DATE PIC X(10).
       
       01 TRANSACTION-LOG.
           05 LOG-ENTRY OCCURS 100 TIMES.
               10 TRANSACTION-DATE    PIC X(10).
               10 TRANSACTION-TYPE    PIC X(1).
               10 TRANSACTION-AMOUNT  PIC 9(8)V99.
               10 TRANSACTION-DESC     PIC X(30).
       
       PROCEDURE DIVISION.
       
       METHOD-ID. INITIALIZE-ACCOUNT.
       DATA DIVISION.
       LINKAGE SECTION.
       01 ACCOUNT-NUM          PIC 9(10).
       01 HOLDER-NAME          PIC X(50).
       01 INITIAL-BALANCE      PIC 9(10)V99.
       01 ACCOUNT-TYPE-PARAM   PIC X(10).
       
       PROCEDURE DIVISION USING ACCOUNT-NUM
                                HOLDER-NAME
                                INITIAL-BALANCE
                                ACCOUNT-TYPE-PARAM.
           MOVE ACCOUNT-NUM TO ACCOUNT-NUMBER
           MOVE HOLDER-NAME TO ACCOUNT-HOLDER
           MOVE INITIAL-BALANCE TO ACCOUNT-BALANCE
           MOVE ACCOUNT-TYPE-PARAM TO ACCOUNT-TYPE
           
           *> Use intrinsic functions for date handling
           MOVE FUNCTION CURRENT-DATE(1:10) TO CREATION-DATE
           MOVE FUNCTION CURRENT-DATE(1:10) TO LAST-TRANSACTION-DATE
           
           DISPLAY 'Account initialized: ' ACCOUNT-NUMBER
           
       END METHOD INITIALIZE-ACCOUNT.
       
       METHOD-ID. PROCESS-TRANSACTION.
       DATA DIVISION.
       LINKAGE SECTION.
       01 TRANSACTION-TYPE     PIC X(1).
           88 DEPOSIT          VALUE 'D'.
           88 WITHDRAWAL       VALUE 'W'.
       01 TRANSACTION-AMOUNT   PIC 9(8)V99.
       01 TRANSACTION-DESC     PIC X(30).
       01 TRANSACTION-SUCCESS  PIC X(1).
           88 SUCCESS          VALUE 'Y'.
           88 FAILURE          VALUE 'N'.
       
       PROCEDURE DIVISION USING TRANSACTION-TYPE
                                TRANSACTION-AMOUNT
                                TRANSACTION-DESC
                       RETURNING TRANSACTION-SUCCESS.
           *> Log the transaction
           PERFORM LOG-TRANSACTION
           
           *> Process based on transaction type
           EVALUATE TRUE
               WHEN DEPOSIT
                   IF TRANSACTION-AMOUNT > 0
                       ADD TRANSACTION-AMOUNT TO ACCOUNT-BALANCE
                       SET SUCCESS TO TRUE
                   ELSE
                       SET FAILURE TO TRUE
                   END-IF
               
               WHEN WITHDRAWAL
                   IF TRANSACTION-AMOUNT <= ACCOUNT-BALANCE AND TRANSACTION-AMOUNT > 0
                       SUBTRACT TRANSACTION-AMOUNT FROM ACCOUNT-BALANCE
                       SET SUCCESS TO TRUE
                   ELSE
                       SET FAILURE TO TRUE
                   END-IF
               
               WHEN OTHER
                   SET FAILURE TO TRUE
           END-EVALUATE
           
           *> Update last transaction date
           MOVE FUNCTION CURRENT-DATE(1:10) TO LAST-TRANSACTION-DATE
           
       END METHOD PROCESS-TRANSACTION.
       
       METHOD-ID. LOG-TRANSACTION.
       DATA DIVISION.
       LINKAGE SECTION.
       01 TRANSACTION-TYPE     PIC X(1).
       01 TRANSACTION-AMOUNT   PIC 9(8)V99.
       01 TRANSACTION-DESC     PIC X(30).
       
       PROCEDURE DIVISION USING TRANSACTION-TYPE
                                TRANSACTION-AMOUNT
                                TRANSACTION-DESC.
           *> Find next available log entry
           PERFORM VARYING LOG-INDEX FROM 1 BY 1
               UNTIL LOG-INDEX > 100 OR LOG-ENTRY(LOG-INDEX) = SPACES
               CONTINUE
           END-PERFORM
           
           *> Add transaction to log
           IF LOG-INDEX <= 100
               MOVE FUNCTION CURRENT-DATE(1:10) TO TRANSACTION-DATE(LOG-INDEX)
               MOVE TRANSACTION-TYPE TO TRANSACTION-TYPE(LOG-INDEX)
               MOVE TRANSACTION-AMOUNT TO TRANSACTION-AMOUNT(LOG-INDEX)
               MOVE TRANSACTION-DESC TO TRANSACTION-DESC(LOG-INDEX)
           END-IF
           
       END METHOD LOG-TRANSACTION.
       
       END CLASS MODERN-BANK-ACCOUNT.

COBOL-2014 includes enhanced intrinsic functions like FUNCTION CURRENT-DATE for better date handling, improved EVALUATE statements for cleaner conditional logic, and better support for modern programming practices. The standard also includes enhanced Unicode support and improved integration capabilities for working with modern systems and databases.

Standards Compliance

1. Writing Standards-Compliant Code

Writing standards-compliant COBOL code ensures portability, maintainability, and compatibility across different systems. This involves following the official syntax rules, using approved language constructs, and avoiding vendor-specific extensions that might not be available on other platforms.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. STANDARDS-COMPLIANT-EXAMPLE.
       AUTHOR. JOHN DOE.
       DATE-WRITTEN. 2024-01-15.
       *> Following COBOL-2014 standard for maximum compatibility
       
       ENVIRONMENT DIVISION.
       CONFIGURATION SECTION.
       SOURCE-COMPUTER. IBM-390.
       OBJECT-COMPUTER. IBM-390.
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       *> Use standard data types and picture clauses
       01 CUSTOMER-RECORD.
           05 CUSTOMER-ID          PIC 9(8).
           05 CUSTOMER-NAME        PIC X(50).
           05 CUSTOMER-ADDRESS.
               10 STREET-ADDRESS   PIC X(40).
               10 CITY             PIC X(20).
               10 STATE            PIC X(2).
               10 ZIP-CODE         PIC X(10).
           05 CUSTOMER-BALANCE     PIC 9(10)V99.
           05 ACCOUNT-STATUS       PIC X(1).
               88 ACTIVE           VALUE 'A'.
               88 INACTIVE         VALUE 'I'.
               88 SUSPENDED        VALUE 'S'.
       
       *> Use standard 88-level conditions
       01 PROCESSING-CONTROLS.
           05 RECORD-COUNT        PIC 9(6) VALUE ZERO.
           05 TOTAL-BALANCE       PIC 9(12)V99 VALUE ZERO.
           05 END-OF-FILE         PIC X(1) VALUE 'N'.
               88 EOF             VALUE 'Y'.
               88 NOT-EOF         VALUE 'N'.
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           PERFORM INITIALIZE-PROCESSING
           PERFORM PROCESS-CUSTOMERS
           PERFORM DISPLAY-SUMMARY
           STOP RUN.
       
       INITIALIZE-PROCESSING.
           MOVE ZERO TO RECORD-COUNT
           MOVE ZERO TO TOTAL-BALANCE
           SET NOT-EOF TO TRUE
           DISPLAY 'Starting customer processing'.
       
       PROCESS-CUSTOMERS.
           PERFORM VARYING CUSTOMER-ID FROM 10000001 BY 1
               UNTIL CUSTOMER-ID > 10000010
               PERFORM PROCESS-SINGLE-CUSTOMER
           END-PERFORM.
       
       PROCESS-SINGLE-CUSTOMER.
           ADD 1 TO RECORD-COUNT
           
           *> Use standard conditional logic
           EVALUATE CUSTOMER-ID MOD 3
               WHEN 0
                   SET ACTIVE TO TRUE
                   MOVE 5000.00 TO CUSTOMER-BALANCE
               WHEN 1
                   SET INACTIVE TO TRUE
                   MOVE 1000.00 TO CUSTOMER-BALANCE
               WHEN 2
                   SET SUSPENDED TO TRUE
                   MOVE 0 TO CUSTOMER-BALANCE
           END-EVALUATE
           
           ADD CUSTOMER-BALANCE TO TOTAL-BALANCE
           
           DISPLAY 'Customer ' CUSTOMER-ID ' processed with status ' ACCOUNT-STATUS.
       
       DISPLAY-SUMMARY.
           DISPLAY 'Processing Summary:'
           DISPLAY 'Records processed: ' RECORD-COUNT
           DISPLAY 'Total balance: ' TOTAL-BALANCE.

Standards-compliant code follows the official COBOL syntax exactly, uses standard data types and picture clauses, employs proper 88-level conditions for readability, and avoids vendor-specific extensions. The code uses structured programming constructs like PERFORM VARYING and EVALUATE instead of GO TO statements, making it more maintainable and portable.

2. Avoiding Non-Standard Extensions

Many COBOL implementations include vendor-specific extensions that provide additional functionality but reduce portability. While these extensions can be useful, they should be avoided in code that needs to run on multiple platforms or be maintained by different teams.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. PORTABLE-COBOL-EXAMPLE.
       *> This example avoids vendor-specific extensions for maximum portability
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       *> Use standard data definitions
       01 CURRENT-DATE.
           05 YEAR               PIC 9(4).
           05 MONTH              PIC 9(2).
           05 DAY                PIC 9(2).
       
       01 CURRENT-TIME.
           05 HOUR               PIC 9(2).
           05 MINUTE             PIC 9(2).
           05 SECOND             PIC 9(2).
       
       *> Avoid vendor-specific data types
       *> Instead of: 01 BINARY-NUMBER PIC S9(9) COMP.
       *> Use standard: 01 BINARY-NUMBER PIC S9(9) COMP-5.
       01 CALCULATION-RESULT    PIC S9(9) COMP-5.
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           PERFORM GET-CURRENT-DATE-TIME
           PERFORM PERFORM-CALCULATIONS
           PERFORM DISPLAY-RESULTS
           STOP RUN.
       
       GET-CURRENT-DATE-TIME.
           *> Use standard ACCEPT statement instead of vendor-specific functions
           ACCEPT YEAR FROM DATE YYYYMMDD
           ACCEPT MONTH FROM DATE YYYYMMDD(5:2)
           ACCEPT DAY FROM DATE YYYYMMDD(7:2)
           
           ACCEPT HOUR FROM TIME
           ACCEPT MINUTE FROM TIME(3:2)
           ACCEPT SECOND FROM TIME(5:2)
           
           DISPLAY 'Current date: ' YEAR '-' MONTH '-' DAY
           DISPLAY 'Current time: ' HOUR ':' MINUTE ':' SECOND.
       
       PERFORM-CALCULATIONS.
           *> Use standard arithmetic operations
           COMPUTE CALCULATION-RESULT = (YEAR * 10000) + (MONTH * 100) + DAY
           
           *> Avoid vendor-specific mathematical functions
           *> Use standard COBOL arithmetic instead
           IF CALCULATION-RESULT > 20240101
               DISPLAY 'Date is in the future'
           ELSE
               DISPLAY 'Date is in the past or present'
           END-IF.
       
       DISPLAY-RESULTS.
           DISPLAY 'Calculation result: ' CALCULATION-RESULT.
       
       *> Avoid vendor-specific program termination
       *> Use standard STOP RUN instead of vendor-specific EXIT statements

This example demonstrates how to write portable COBOL code by using standard language features instead of vendor-specific extensions. It uses standard ACCEPT statements for date/time handling, standard arithmetic operations instead of vendor-specific functions, and standard program termination. This approach ensures the code will work on any COBOL implementation that follows the standard.

Migration Between Standards

1. Upgrading from Older Standards

Migrating COBOL code from older standards to newer ones can provide access to modern features and improved capabilities. However, this process requires careful planning to ensure compatibility and maintain existing functionality while taking advantage of new features.

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. MIGRATION-EXAMPLE.
       *> Example of migrating from COBOL-74 to COBOL-2014
       
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       *> Old COBOL-74 style (commented out)
       *> 01 CUSTOMER-RECORD.
       *>     05 CUSTOMER-NUMBER    PIC 9(6).
       *>     05 CUSTOMER-NAME      PIC X(30).
       *>     05 CUSTOMER-BALANCE   PIC 9(8)V99.
       
       *> New COBOL-2014 style with enhanced features
       01 CUSTOMER-RECORD.
           05 CUSTOMER-NUMBER    PIC 9(8).  *> Increased size for modern systems
           05 CUSTOMER-NAME       PIC X(50). *> Increased for international names
           05 CUSTOMER-BALANCE    PIC 9(12)V99. *> Increased for larger amounts
           05 ACCOUNT-TYPE        PIC X(10).
               88 CHECKING        VALUE 'CHECKING'.
               88 SAVINGS         VALUE 'SAVINGS'.
               88 BUSINESS        VALUE 'BUSINESS'.
           05 CREATION-DATE       PIC X(10).
           05 LAST-UPDATE-DATE   PIC X(10).
       
       PROCEDURE DIVISION.
       MAIN-PROCEDURE.
           PERFORM INITIALIZE-PROCESSING
           PERFORM PROCESS-CUSTOMERS
           PERFORM DISPLAY-RESULTS
           STOP RUN.
       
       INITIALIZE-PROCESSING.
           *> Use modern intrinsic functions
           MOVE FUNCTION CURRENT-DATE(1:10) TO CREATION-DATE
           MOVE FUNCTION CURRENT-DATE(1:10) TO LAST-UPDATE-DATE
           
           DISPLAY 'Processing started at: ' CREATION-DATE.
       
       PROCESS-CUSTOMERS.
           *> Old COBOL-74 style (commented out)
           *> PERFORM PROCESS-SINGLE-CUSTOMER UNTIL END-OF-FILE
           
           *> New COBOL-2014 style with structured loops
           PERFORM VARYING CUSTOMER-NUMBER FROM 10000001 BY 1
               UNTIL CUSTOMER-NUMBER > 10000010
               PERFORM PROCESS-SINGLE-CUSTOMER
           END-PERFORM.
       
       PROCESS-SINGLE-CUSTOMER.
           *> Use modern conditional logic
           EVALUATE CUSTOMER-NUMBER MOD 3
               WHEN 0
                   SET CHECKING TO TRUE
                   MOVE 2500.00 TO CUSTOMER-BALANCE
               WHEN 1
                   SET SAVINGS TO TRUE
                   MOVE 5000.00 TO CUSTOMER-BALANCE
               WHEN 2
                   SET BUSINESS TO TRUE
                   MOVE 10000.00 TO CUSTOMER-BALANCE
           END-EVALUATE
           
           *> Update timestamp using modern functions
           MOVE FUNCTION CURRENT-DATE(1:10) TO LAST-UPDATE-DATE
           
           DISPLAY 'Customer ' CUSTOMER-NUMBER ' processed'.
       
       DISPLAY-RESULTS.
           DISPLAY 'Processing completed at: ' FUNCTION CURRENT-DATE(1:10).

This migration example shows how to upgrade from older COBOL standards to modern ones. The old COBOL-74 style uses basic data structures and simple loops, while the new COBOL-2014 version includes enhanced data types, modern intrinsic functions, structured conditional logic with EVALUATE, and improved date/time handling. The migration maintains the same functionality while providing access to modern features.

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