FEATURE ARTICLE 1: POPULATION BY AGE AND SEX, AUSTRALIA, STATES AND TERRITORIES


INTRODUCTION

This article summarises features of the data presented in the spreadsheets and datacubes accompanying this release which present the estimated resident population (ERP) of Australian states and territories by single year of age and by sex, as at 30 June.


MEDIAN AGE

The median age (the age at which half the population is older and half is younger) of the Australian population has increased by 2 years over the last two decades, from 35 years at 30 June 1998 to 37 years at 30 June 2018. Between 30 June 2017 and 30 June 2018 the median age remained steady at 37 years.

Tasmania experienced the largest increase in median age over the last 20 years, increasing by 6 years from 36 years in 1998 to 42 years in 2018. Interstate migration of younger adults from Tasmania to the Australian mainland has contributed to this accelerated ageing. For further information, see Migration, Australia (cat. no. 3412.0).

At 30 June 2018, Tasmania had the highest median age of all the states and territories (42 years), followed by South Australia (40 years). The Northern Territory had the lowest median age (33 years), followed by the Australian Capital Territory (35 years).

AGEING POPULATION

Over the next several decades, population ageing will have a range of implications for Australia, including; health, size of the working-age population, housing and demand for skilled labour.

Like most developed countries, Australia's population is ageing as a result of sustained low fertility and increasing life expectancy. This has resulted in proportionally fewer children (under 15 years of age) in the population and a larger proportion of people aged 65 and over.

CHILDREN (AGED 0-14 YEARS)

In the 20 years between 1998 and 2018, the proportion of children decreased from 21.0% to 18.8% of the total population.

In the 12 months to 30 June 2018, the total number of children increased by 1.4% (63,100 people) compared with an increase of 1.5% (66,500 people) in the previous year. Over this period, the number of 0-4 year olds increased by 3,200 (0.2%), 5-9 year olds increased by 17,600 (1.1%), and those aged between 10-14 years increased by 42,400 (2.9%).

In the year ended 30 June 2018, the Australian Capital Territory recorded the largest percentage increase in the number of children (2.6%), followed by Victoria (1.8%), New South Wales and Queensland (both 1.4%). The Northern Territory was the only state or territory to report a percentage decrease (0.6%).


WORKING-AGE POPULATION (AGED 15-64 YEARS)

At 30 June 1998, two out of three people were aged between 15 and 64 years - usually referred to as the 'working-age population'. This proportion increased to a high of 67.5% in 2009, before declining to 65.5% by 30 June 2018.

In the 12 months to 30 June 2018, the Australian working-age population increased by 1.3% (or 203,200 persons). During this period, the working-age population in Victoria grew by 2.1%, higher than the national growth rate. In contrast, the population of 15-64 year olds declined in the Northern Territory by 0.5%.

There were 285,400 young people aged 15 years who entered the working-age population while 253,300 people turned 65 years and left the working-age population in the year ended 30 June 2018.



Over the 20 years to 30 June 2018, the working-age population grew by 31.9%, slower than the growth of the remaining population (39.1%) The slower growth in the working-ages has occurred since 2010.

Over the five years to 30 June 2018, the working-age population grew by 6.2%, compared to 11.8% for the remainder. The main contributor to the increased growth of the non-working-ages was the growth in the population aged 65 and over.


PEOPLE AGED 65 YEARS AND OVER

Over the 20 years between 1998 and 2018, the proportion of the population aged 65 years and over increased from 12.2% to 15.7%. This group is projected to increase more rapidly over the next decade, as further cohorts of baby boomers (those born between the years 1946 and 1964) turn 65. Currently, only seven of these cohorts by birth years have reached age 65 and there are 12 remaining.

Notably, in the past 20 years, the proportion of the Northern Territory's population aged 65 years and over increased from 3.3% to 7.6% due, in part to an increasing life expectancy.



In the 12 months to 30 June 2018, the number of people aged 65 years and over increased by 124,200 people, representing a 3.3% increase.

In the 12 months to 30 June 2018, the population aged 65 years and over grew in all states and territories. The largest increase in this group was in the Northern Territory (5.8%), followed by Western Australia (4.0%), and the Australian Capital Territory (3.9%).


PEOPLE AGED 85 YEARS AND OVER

Over the past two decades, the number of people aged 85 years and over increased by 125.1%, compared with a total population growth of 34.3% over the same period.

In the year ending 30 June 2018, the number of people aged 85 years and over increased by 10,800 people (2.2%) to reach 503,700. There were more females (312,400) than males (191,300) in this age group which reflects the higher life expectancy for females.

Over the same period, the largest percentage increases of people aged 85 years and over occurred in the Northern Territory (6.1%), followed by Western Australia (3.6%), Victoria (2.6%), the Australian Capital Territory (2.3%), Queensland (2.2%), New South Wales (1.9%), Tasmania (1.7%) and South Australia (0.9%).


SEX RATIOS

The sex ratio is the number of males per 100 females in a population. The sex ratio at birth is approximately 106 males per 100 females. Higher male mortality rates at younger ages result in the ratio approaching 100 by the age of 30. Overseas migration can influence the sex ratio, especially in the working ages where there has historically been a greater proportion of male migrants. Above age 70, the sex ratio reduces markedly due to the impact of higher male mortality in this population group.

At 30 June 2018, the sex ratio of the total population of Australia was 98.4 males per 100 females. At age 0, the sex ratio for Australia at 30 June 2018 was 105.7 males per 100 females. The larger amount of males at younger ages contrasts with the opposite situation in the older ages, which is attributed to female longevity.

At 30 June 2018, the Northern Territory and Western Australia had the highest sex ratios out of the states and territories, of 107.7 and 100.1 respectively. South Australia had the lowest ratio at 97.7, followed by Victoria, Queensland, Tasmania and the Australian Capital Territory all with ratios of 98.0.

INTERNATIONAL COMPARISON

Population ageing is a notable demographic characteristic of most developed countries. It is related to both sustained low fertility which results in proportionately fewer children, and increasing life expectancy which results in proportionately more elderly people. In Japan, Italy, France, Greece, Sweden, Canada, United Kingdom and Hong Kong (Special administrative region (SAR) of China), the number of people aged 65 years and over already exceeds the number of children aged 0-14 years. In Australia, based on the latest Series B population projections, the number of people aged 65 years and over is projected to exceed the number of children aged 0-14 years around the year 2034. For more information, see Population Projections, Australia, 2017 (base) - 2066 (cat. no. 3222.0).

According to United Nations projections, all of the 20 countries selected for analysis in the table below are projected to experience an increase in the proportion of people aged 65 and over to 2020. In all of the selected countries except for Canada, United Kingdom, Hong Kong and Sweden, this increase in older population is accompanied by a decrease in the 0-14 year old population.

According to ABS projection Series B, the proportion of children 0-14 years in the Australian population is projected remain constant between 2015 and 2020, at 18.9%, while the proportion of people aged 15-64 years is projected to decrease by 1.1 percentage points, from 66.2% to 65.1%. The proportion of people aged 65 years and over is projected to increase by 1.1 percentage points, from 14.9% to 16.0%.

In 2015, the age structure of Australia's population was similar to that of New Zealand and the United States of America. Generally, the European countries and Japan had smaller proportions of children and higher proportions of older people than Australia. In contrast, developing countries tended to have proportionally more children and far fewer older people, generally reflecting higher fertility rates and lower life expectancies than those experienced in Australia.

Population age structure, International comparison(a)(b) - at 30 June
	2015				2020				2015 - 2020
	Aged 0-14 years	Aged 15-64 years	Aged 65 years and over	Median Age	Aged 0-14 years	Aged 15-64 years	Aged 65 years and over	Median Age	Total fertility rate(c)	Life expectancy(d)
Selected Countries	%	%	%	years	%	%	%	years	rate	years
Australia	18.9	66.2	14.9	37.2	18.9	65.1	16.0	37.3	1.8	83.2
Canada	16.0	67.9	16.1	40.5	16.1	65.6	18.3	41.4	1.6	82.6
China (excl. SARs and Taiwan)	17.7	72.6	9.7	37.0	17.5	70.4	12.2	38.7	1.6	76.5
France	18.3	62.8	18.9	41.2	17.8	61.5	20.7	42.0	2.0	82.8
Greece	14.5	65.5	19.9	43.3	13.7	65.1	21.1	45.3	1.3	81.5
Hong Kong (SAR of China)	11.2	73.6	15.2	43.2	12.7	69.2	18.1	44.8	1.3	84.2
India	28.7	65.7	5.6	26.7	26.6	66.9	6.6	28.2	2.3	68.9
Indonesia	27.9	67.0	5.1	28.0	26.4	67.8	5.8	29.3	2.3	69.4
Italy	13.7	63.9	22.4	45.9	13.2	62.8	23.9	47.9	1.5	83.3
Japan	13.0	61.0	26.0	46.3	12.7	59.1	28.2	48.2	1.5	84.0
Korea (South)	13.9	73.1	13.0	40.8	13.2	71.1	15.7	43.4	1.3	82.4
Malaysia	25.0	69.2	5.9	27.7	23.6	69.4	7.0	29.9	2.0	75.5
New Zealand	20.0	65.4	14.6	37.3	19.6	64.0	16.3	37.9	2.0	82.1
Papua New Guinea	36.6	59.7	3.6	21.7	34.9	61.0	4.1	22.6	3.6	65.8
Philippines	32.2	63.2	4.6	24.1	31.0	63.8	5.2	25.2	2.9	69.3
Singapore	15.5	72.8	11.7	40.0	14.3	70.7	15.0	42.4	1.3	83.3
South Africa	29.3	65.6	5.1	26.1	28.4	65.9	5.7	27.3	2.4	63.7
Sweden	17.3	63.1	19.6	40.9	17.8	61.9	20.3	41.0	1.9	82.7
United Kingdom	17.6	64.3	18.1	40.2	17.9	63.1	19.0	40.8	1.9	81.8
United States of America	19.2	66.1	14.6	37.6	18.6	64.8	16.6	38.3	1.9	79.6
Vietnam	23.1	70.2	6.7	30.4	22.9	69.0	8.1	32.6	2.0	76.6
World	26.1	65.6	8.3	29.6	25.5	65.1	9.4	30.9	2.5	71.9
(a) Selected countries included major OECD countries, the world's most populous countries, Australia's closest neighbours and trading partners.
(b) International data are United Nations medium variant projections. Australian data are ABS medium series (Series B) projections
(c) Births per woman. United Nations data are medium variant projections for the period 2015-2020.
(d) Life expectancy at birth. United Nations data are medium variant projections for the period 2015-2020, for males and females combined.
Note: All international figures for both 2015 and 2020, total fertility rates and life expectancy have been sourced from United Nations, Department of Economics and Social Affaris, Population Division (2017) World Population Prospects: The 2017 Revision, custom data acquired via website. Australian 2015 estimates are from ABS, Australian Demographic Statistics (cat. no. 3101.0) and Australian 2020 population projections are medium series (Series B) from Population Projections, Australia 2017 (base) - 2066 (cat. no. 3222.0).