Kōrero: Population change

During the post-Second World War baby boom New Zealand had the highest fertility rate among developed countries. From the 1970s the boom gave way to low fertility rates – they were just below replacement level in the early 2000s. Life expectancy was high, and numbers of older people were expected to grow in the 21st century.

Story by Ian Pool
Te āhua nui: Hannahs shoe-factory staff, Wellington, 1930s

Story Summary

Ngā whakaahua

Population growth

Between the late 1700s and the early 2000s the world’s population increased from just under 1 billion to more than 6 billion. In the same period New Zealand’s population increased 40-fold, from 70,000–90,000 people to over 4 million.

Migration was the main cause of population growth from the 1850s to the 1870s. After this, natural increase (births minus deaths) was the main cause.


Pākehā fertility (the number of children per woman) was very high in the 19th century, when most women married, and at young ages. From the 1840s to the 1870s each woman had an average of seven live births. Pākehā fertility rates then fell, while Māori rates stayed high. The Pākehā rate increased again from the 1940s to the early 1970s – a period called the baby boom.

From the 1970s new contraceptive methods were available, and the fertility rate for Māori and Pākehā fell. In 2006 the fertility rate was 2.01 births per woman – just below replacement level (2.1 births per woman).


In the 19th century Pākehā had high life expectancy by world standards. However, the Māori death rate was high, especially for children, and the Māori population fell, mostly because of diseases introduced by Pākehā. From the later 1890s the Māori population began to increase again.

The main causes of death have changed from communicable diseases such as measles and tuberculosis to non-communicable diseases such as cancer. This change happened for Pākehā from the late 19th century and for Māori from the mid-20th century.

Age structure

When fertility is high and death rates decline – such as during the baby boom – a high proportion of the population are children. This means relatively fewer people working and more children to support, compared with periods of low fertility. In the 21st century the proportion of the population aged 65 and over was increasing. In the future there are likely to be fewer people paying tax, and more people receiving government superannuation and using health and social services.

Geographic distribution

New Zealand was founded as a farming nation, but by the time of the 1916 census more people lived in urban areas than rural areas. Employment patterns changed from farming, forestry, fishing and mining to manufacturing and services.

In the late 19th century most people were in the South Island, but since then most people have lived in the North Island. In 2006 one-third of the population lived in Auckland.

Me pēnei te tohu i te whārangi:

Ian Pool, 'Population change', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/mi/population-change (accessed 20 June 2018)

Story by Ian Pool, published 5 May 2011