Age profile

This section describes the age structure of Aotearoa New Zealand’s population. It also explains why children and older adults are more at risk from environmental hazards.

Our population age structure

In 2018, in the total population:

• 19.6% were children (aged 0–14 years)
• 65.1% were working age (aged 15–64 years)
• 15.2% were aged 65 years and over (65+ years).

An ageing population

Our population is getting older. The median age of New Zealanders increased from 35.9 years in 2006, to 38.0 years in 2013 and 37.4 years in 2018.

Older adults make up an increasingly large proportion of the New Zealand population:

• 2006: 495,600 people aged 65+ years (12.3% of the population)
• 2013: 607,000 people aged 65+ years (14.3% of the population)
• 2018: 715,200 people aged 65+ years (15.2% of the population).

Figure 1: Percentage (%) of New Zealand's population aged 65+ years and 85+ years, 1981–2018

Older adults will make up an increasingly large proportion of the population over the next 20–30 years. The population aged 65+ years is projected to almost double to 1.37 million by 2043 (23.1% of the total population) [1].

The number of people aged 85+ years is also expected to increase significantly. The population aged 85+ years was about 84,400 in 2018 (1.8% of the population). This age group is projected to more than triple to 260,600 people by 2043 (4.4% of the population).

Regional differences in age structure

Some territorial authorities in New Zealand have a younger population (Figure 2), while others have an older population (Figure 3).

Figure 2: Children aged 0–14 years, by territorial authority, 2018 (% of the total population) 

Figure 3: Older adults aged 65+ years, by territorial authority, 2018 (% of the total population) 

Younger and older people are more vulnerable to environmental risks

Infants and children are particularly affected by the environment due to several reasons:

• Children are still developing and growing, which makes them more susceptible to toxins and illness.
• Children’s breathing rate is higher than adults, making them more susceptible to air pollution.
• Children have limited mobility, so spend longer in one place and must depend on others to move them out of dangerous areas.
• Their behaviour includes lots of hand-to-mouth activity, which exposes them more to some hazards (eg, lead from soil).
• Children spend most of their time in the home environment.
• Children’s younger age and longer life expectancy means that they may yet be affected by some hazardous substances with long lag (latency) periods.

Older adults can also be more affected by environmental hazards.

• Older adults may have limited mobility, strength and balance. This means they are in one place for longer periods, and depend on others to move them out of dangerous areas. 
• Older adults have higher rates of chronic disease, which can make them more sensitive to environmental hazards like air pollution. For example, days with lots of air pollution will be tolerated less by people with chronic lung disease, because their lungs are already working hard to cope at ‘normal’ levels of air pollution. 
• Older adults are more sensitive to dehydration on very hot days, and the effects of cold on cold days.

Information about the data

Census usually resident population, by age
Source: New Zealand 2018 Census of Populations and Dwellings

Definition: This data comes from the 2018 Census of Populations and Dwellings. The 2018 Census had a lower than expected response rate, resulting in Stats NZ introducing new methods to produce the dataset, including using data from alternative sources. Stats NZ and the 2018 Census External Data Quality Panel (EDQP) have produced a rating system to help the users understand the quality-related issues and impacts of the 2018 Census dataset.

EHI have decided to update the population statistics on this webpage, based on the documentation relating to these indicators. The Census variable of 'age' had an EDQP rating of 'very high' at the national and regional council level [2]. Further information about the Stats NZ and EDQP documentation can be at:  https://www.stats.govt.nz/2018-census/data-quality-for-2018-census

National population projections, by age and sex
Source: NZ.Stat website

Definition: This data comes from the NZ.Stat website. The data tables contain 2016-based projections of the population usually living in New Zealand (released October 2016). These projections have as a base the provisional estimated resident population of New Zealand at 30 June 2016. Stochastic (probabilistic) population projections are produced to give measures of uncertainty. the data provided on this webpage refer to the 50th percentiles (ie, median) values.

References

1. Statistics New Zealand. 2016. National Population Projections, by age and sex, 2016(based)-2068 [data tables]. Wellington: Stats NZ. URL: http://nzdotstat.stats.govt.nz/wbos/Index.aspx?DataSetCode=TABLECODE7542# 

2. EDQP. 2019. Initial Report of the 2018 Census External Data Quality Panel. URL: https://www.stats.govt.nz/reports/initial-report-of-the-2018-census-external-data-quality-panel (accessed 24/08/20).