Pigs are mainly concentrated in the dairying (especially buttermaking) districts. Thus, since the industry expanded in the thirties, between 55 and 60 per cent of all pigs have been produced in the Auckland Province. The general pattern of distribution has not changed in the last decade; and though intensive dairying areas have changed to milk tanker, the later settled districts in Northland, Coromandel, and the Central Plateau of the North Island balanced the trend. In the last year or two the proportion of pigs produced in the South Island has increased slightly, due to expansion in Marlborough, Nelson, and Westland. The production in the southern half of the South Island remains much below the prewar figure.