New information following the change in COVID-19 alert levels.

About the project

What's in a name?

This project, funded by the Royal Society of New Zealand’s Marsden fund, has as its formal title ‘The subnational mechanisms of the ending of population growth. Towards a theory of depopulation’. However the research team finds its Maori translation: Tai Timu Tangata. Tahoa e? (The ebbing of the human tide. What will it mean for the people?) both inspiring and encouraging, because the work is not only about describing and understanding the subnational drivers and processes brining about the ending of population growth, but equally it is about whether depopulation can be halted or reversed—and if not, what it will mean for so much that we take for granted?

The work is also very much about trying to communicate some issues that many people appear to find almost preposterous: that after a century of hand-wringing about global population growth, that growth is coming to an end—and is highly likely to do so within the life time of children being born today. The fact that the trend is well under way and being closely monitored by the world’s leading population, economic and social institutions, including the World Bank, the International Monetary Fund (IMF), the OECD, and the United Nations, should give pause for thought.

Population growth

Although New Zealand’s population continues to grow at around the global growth rate—largely due to Auckland and its relatively youthful population, many of its rural and smaller urban towns are already showing evidence of the permanent ending of growth/onset of depopulation which is accompanied by, and in some cases driven by, population ageing. Indeed one-third of New Zealand’s territorial authority areas declined between 1996 and 2013, and both projections and our analysis suggests that, for most, growth is unlikely to resume in any magnitude. This is precisely what we have observed in all countries that are now declining at national level, like Japan and several European countries, and at sub-national level in these and many others.

Given our past preoccupations with growth, the ending of growth will surely usher in a great many challenges. According to a broad international literature it will almost certainly affect the ability of governments both local and central to maintain, let alone build, local infrastructure (think roads, schools, hospitals), along with negatively affecting the value of our houses and businesses, and ultimately our ability to pay the rates needed to provide that infrastructure. We need, with some urgency, to begin developing policy responses to this emerging situation. Yet, when we look at the literature, we don’t find any theories or sound premises for policy change that would provide councils and governments with the support they need to make the changes. Without this grounded, evidence-based support, governments making changes will render themselves unpopular with voters and vulnerable to being voted out, while if their competitors deny the changes we are talking about, even more damaging policies are likely to be put in place.

Project context

In observing this overall situation the Tai Timu Tangata team felt that New Zealand would make a useful case study. The project’s abstract, given in the text box on the right explains the broad issues. Below are the project’s main operational aspects:

In the context of the global ending of population growth around the end of the 21st Century, the Tai Timu Tangata project has three main aims: (1) to investigate and specify the demographic thresholds which signal the onset of population decline at sub-national level; (2) to determine the extent to which the crossing of these thresholds is associated with industrial change or is unrelated; and (3) to draw these findings together in a first-order theory of depopulation which will both broaden present theoretical understandings and assist practical responses to these trends.

We use empirical data for New Zealand, a country still growing strongly at national level whilst succumbing to the end of growth in around one-third of its 67 territorial authority areas, to test the project’s central proposition that the end of growth will unfold sequentially from rural to urban locales, the speed and severity of the trends magnified by unprecedented demographic-economic interactions.

The primary goals of the project are to:

1) Develop an automated database of demographic, migration, and labour market (industry, labour force status, qualifications) data for the 67 TAs and their Regional Council (RC) areas (Year one)

2) Test three operational hypotheses that identify, model and classify the demographic thresholds of subnational decline (Years one and two)

3) Determine the extent to which industrial change is associated with demographic change and support the findings with an analysis of job loss and firm start-up data, and labour force and qualifications data (Years two and three)

4) Develop our model of inverse cumulative causation (Years two and three)

5) Test three further operational hypotheses to determine the counterfactual conditions (mortality, fertility and migration—and by extrapolation, industry) under which local growth could resume and be sustained (Years two and three)

6) Test our findings against the ongoing validity of concepts central to demographic and mobility theories, and theorise our conclusions (Year three).

Project abstract

Population growth is theorised to cease globally around 2100, resulting in irreversible population shrinkage in most countries. Currently recognised only when it occurs at national level, the ending of growth has not yet been theorised to assist policy responses. Empirical evidence shows that the onset of decline begins sub-nationally, at different times, in different ways. Subnational decline is also increasingly driven by a new set of dynamics: negative natural increase (deaths exceeding births) combining with the old form of decline – net migration loss. This project will integrate demographic and mobility transition theories to develop a first-order theory of depopulation, proposing that the end of growth unfolds sequentially from rural to urban locales, the speed and severity of the trends magnified by unprecedented demographic-economic interactions. Our multi-disciplinary team will generate a substantive account of these mechanisms for New Zealand, a country still growing strongly at national level, but where decline is already the case in one-third of the 67 Territorial Authority Areas. Central to the analysis will be a nation-wide study of industrial labour market change, which we posit precedes the new form of decline, and determination of the counterfactual conditions under which growth could continue, locally and nationally.