Input (grade 13): In 1961, the office of the Postmaster General (PMG) introduced the 000 number in major population centres and near the end of the 1980s extended its coverage to nationwide.
Output (grade 12): In 1961, the Postmaster General (PMG) introduced the 000 number in most of the major Australian cities and by the end of the 1980s it had become nation-wide.