New Zealand’s affluent suburbs are overwhelmingly concentrated in Auckland, but a comparison of data from the 2006 and 2013 censuses shows that Auckland’s dominance has slipped somewhat.
The Magnus affluence index evaluates the standing of census area units (CAUs) based on four attributes of households: having high income, income from investments, business or from rents, or a household member having high qualifications, or a managerial or professional occupation. Each CAU is assigned an average composite score based on these four attributes, the 10 per cent of the 1800-odd CAUs in the country with the highest scores (the tenth decile) then being deemed the affluent ones.
Between 2001 and 2006, the number of decile 10 CAUs in Auckland jumped from 86 to 98. But in 2013, this count stood at 91 (Table 1). If we include rural areas adjacent to Auckland’s urban CAUs, then in 2013 Auckland had 95 decile 10 CAUs.
Table 1 Geographical distribution of decile ten affluent areas
|City or area||2001||2006||2013|
Note: area defined as census area unit.
Source: NZ Census, 2001, 2006, 2013
The number of affluent CAUs in Christchurch has leapt from 13 to 20 (or 21 if we include the rural area of West Melton) (Table 1). It is difficult to know what to attribute the change to. Interpreting change in the affluence index is complicated by the number of CAUs increasing over time (due to population growth), and by the geographical definitions of CAUs also changing over time. The Christchurch CAUs elevated to decile 10 status in 2013 are ones that had been decile 9 in 2006. possibly what has happened is that following the earthquake in 2011, some affluent households have been forced to move, and have moved into the formerly decile 9 areas, thus raising the proportion of affluent households there.This hypothesis does not however explain how smaller cities such as Gisborne or Nelson have come to now figure in decile 10, being previously absent. Factors of change in number of CAUs or of definitional change do not at first glance seem to help explain why suburbs in cities like Gisborne or Nelson should have risen in status.