Abstract
In this paper we report on population change and its demographic drivers for 143 New Zealand towns, 132 rural centres and 66 Territorial Authority Areas (TAs), for the period 1976-2013. We undertook the exercise to identify whether New Zealand's towns and rural centres are following their international counterparts in declining from what is proposed as a 'new' and increasingly intractable form of population decline, where net migration loss is accompanied by natural decrease, as opposed to the 'old' form where natural increase is positive but fails to offset net migration loss. We also examined whether 'age-selective migration', as in the migration-driven loss of young people and/or gain of older people, is a major factor driving New Zealand's subnational structural population ageing. We found that the old form of depopulation, net migration loss, was the major determinant of New Zealand's subnational depopulation across the period 1976-2013; also that migration was highly age-selective. In the process, it accelerated the structural ageing of the majority of TAs, towns and rural centres. In 2013, 41 per cent of towns and 29 per cent of rural centres had populations with greater than 20 per cent aged 65+ years (compared with just 15 per cent for Total New Zealand); 85 per cent of towns were older with migration than they would have been in the absence of migration, as were two-thirds of rural centres and four-fifths of TAs. We also found the new, 'dual' form of depopulation to be present, but as yet affecting a relatively small number of towns and rural centres. However, projections at TA level indicate that the shift to natural decrease and the new form of depopulation will soon escalate, the latter becoming the major cause of depopulation by 2043 and the major cause of population change per se. Overall our analysis confirms that migration is not a panacea for growth. Just 39 per cent of towns, 33 per cent of rural centres, and 26 per cent of TAs were larger in 2013 than 1976 as the result of migration. A further 27 per cent of towns, 17 per cent of rural centres, and 36 per cent of TAs also grew across the period, but were smaller with migration than they would have been in its absence; for them, natural increase played the major role in determining growth. Moreover, we found that migration is negatively correlated with natural increase, and, relatedly, that the proportion of women aged 15-44 years heavily determines natural increase. These findings suggest that areas losing their young, reproductive age population are paying the price of the gains made by other areas. These findings have a number of policy implications, all of which point to the need for regionally-specific policies.