A method, apparatus, and article for solving the year 2000 problem involves limited modifications in the data definition portions of the source code and compiler support for processing the modified source code. Fields in the source code that contain a year or date values are identified and, for each such field, the user selects an appropriate technique (for example, expansion, compression or windowing). The user modifies the data definition for each identified field, by adding new attributes to request the selected technique. The user then compiles the program and resolves any ambiguous references to the variables whose definitions were modified. This procedure is applied, module by module, and each processed module is merged into production, after testing, by using a compiler option to disable the use of the new attributes. A compiler option provides for the generation of debugger hooks for each statement that has been affected by modified declarations, which may be used with a suitably equipped debugger or other run-time analysis tool.