4.8 Million New Zealanders by 2051
New Zealand's future demographic outlook is for quite different growth patterns, population dynamics and structural
make-up than that of the previous 50 years, said Government Statistician Brian Pink.
New Zealand's population is projected to be 4.81 million in 2051, according to 2001-base population projections just
released by Statistics New Zealand. This represents an increase of 930,000 or 24 percent from the estimated resident
population of 3.88 million at 30 June 2001.
This projection assumes that New Zealand women will have 1.85 children on average (below the level of 2.1 children per
woman required for the population to replace itself without migration), life expectancy at birth will improve by six
years by 2051, and that there will be net immigration of 5,000 people a year from 2007 – the average annual migration
gain for the last 100 years.
Under this demographic scenario, population growth will slow steadily and substantially in the future, mainly because of
the narrowing gap between births and deaths. The rate of population growth will average 1.2 percent a year between 2001
and 2006, 0.5 percent during the 2020s and just 0.1 percent during 2036–2041. After 2046, the population is projected to
drop slightly as deaths outnumber the combined effect of births and net migration. Births are expected to decrease from
56,000 in 2001 to 50,000 in 2051, while over the same period deaths will more than double from 27,000 to 57,000.
The age structure of New Zealand's population will undergo significant changes, resulting in fewer children, more older
people and further ageing of the population. This reflects the combined impact of sub-replacement fertility, longevity
gains and the ageing of the large birth cohorts of the 1950s–1970s. By 2051, half the New Zealand population will be
older than 45 years, compared with a median age of 35 years in 2001. The projections suggest that higher migration
levels are unlikely to significantly slow the ageing process. With a net migration gain of 20,000 a year the median age
will be 43 years in 2051, while zero net migration gives a median age of 46 years.
The number of children (0–14 years) is projected to decrease from 880,000 in 2001 to 750,000 in 2051, and their share of
the total population is expected to decrease from 23 percent to 16 percent. In contrast, the number of people aged 65+
years is projected to more than double, from 460,000 in 2001 to 1.22 million in 2051. They will make up 25 percent of
the population in 2051, compared with 12 percent in 2001. Within the 65+ age group, there will be almost 140,000 people
aged 90+ years in 2051, nine times the 2001 total of 15,000. Population ageing is also common to other countries. Italy,
Spain, Greece and Japan, which have much lower fertility levels than New Zealand, are all projected to have over
one-third of their population aged 65+ years by 2051.
The working-age population (defined as those aged 15–64 years) is projected to increase by 15 percent from 2.54 million
in 2001 to 2.92 million in 2021. Most of the increase will be in the older half of this age group (40–64 years) as the
large number of people born in the 1950s–1970s move into these ages. The working-age population is expected to decline
after 2021, to 2.84 million people in 2051.
Based on this demographic data, the total dependency ratio (the number of people aged 0–14 years and 65+ years per 100
people aged 15–64 years) will increase from 53 per 100 in 2001 to 69 per 100 in 2051. The 'child' dependency ratio will
fall from 34 to 27 per 100 over this period, while the 'old age' dependency ratio will more than double from 18 to 43
per 100.
Brian Pink Government Statistician