Three colour mixing of 129,211 census enumeration districts on an equal population cartogram — software by author on an Archimedes computer.
This pictures is dominated, almost exclusively, by purples and yellows. Enumeration districts are characterised by either the old, and thus more female, or young, and hence relatively more male, populations. Other colours are extremely rare. In the three colour cube of all possible combinations, the vast majority of districts lie on a single line.The pattern is of the old dominating the South coast and the centres of large cities. The high numbers of females in areas of the aged is due to women living longer than men, as well as carers of the elderly being mostly female.