Four-digit postcodes were introduced throughout Australia on 1 July 1967 in order to simplify the task of mail-sorting for automatic machines. Like radio call signs, Victorian postcodes begin with 3. Melbourne was allocated 3000 and Melbourne General Post Office boxes 3001, with the suburbs following before numbers moved on to the rest of Victoria. Before 1967, Melbourne had a system of postal districts: Central, South Central, North, South, East, West, and South East, introduced in 1928. Within districts, further division was by numbers. Toorak, famously, was S.E.2.