An Insights reader recently wrote in with a thoughtful question: how could we advocate for the release of land in New Zealand cities as a means of tackling the housing affordability crisis and promoting economic growth?
 
They noted that continued growth, driven by population expansion, is not sustainable in the long term. Humanity, in their view, was akin to a single-celled organism in a jar – at some point the needs of a rapidly growing population would eclipse the environment’s ability to support it. 
 
It is a powerful and emotive argument, and one I must confess to having held myself in the past. 
 
Luckily, humans are not bacteria, and the demographic projections for our planet are not nearly as dire as many people think, as this documentary shows.  
 
First, the world’s population is stabilising. Globally, the total number of children being born has peaked, and once you follow through the projections, the population is expected to top out at about nine billion people and then decline (although this is many decades off). 
 
Second, economic growth and development have been vital to bringing this decline in the number of children being born. Having large families is a survival strategy among the poorest of the poor because of high mortality rates and the need for labour in subsistence farming. Yet, history shows that as people gain access to education, medicine and paid work, their reproductive rates decline markedly towards sustainable levels.  
 
Bringing it back to the New Zealand context, we have a growing population which needs to be housed, which will consume more resources such as land. Our country is bigger than England, but our population is 7 per cent of theirs, and our urban areas only account for 0.8 per cent of total land use in New Zealand. We are not even close to filling the jar.
 
Our total population is also boosted by the baby boomer bulge and, once this is no longer with us, many of the pressures we face in areas such as housing will probably ease.  
 
Some may use this as a justification to cap urban growth, but the burden this would put on the economy and the working-age population through increased house prices and higher living costs would severely curtail our ability to care for the baby boomers as they move into retirement.  
 
Economic growth heedless to the need to preserve the environment is a one-way street to ruin. But equally, veering in the opposite direction would consign us to an existence akin to that experienced by people in North Korea.