FEATURE ARTICLE: 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. The spreadsheets include median ages, mean ages and sex ratios. Estimates up to June 2011 are final and those for June 2012 and June 2013 are revised whilst those for June 2014 and June 2015 are preliminary.


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 3.0 years over the last two decades, from 34 years at 30 June 1995 to 37 years at 30 June 2015. Between 30 June 2014 and 30 June 2015 the median age remained steady at 37 years.

Tasmania experienced the largest increase in median age over the last 20 years, increasing by 8 years from 34 years in 1995 to 42 years in 2015. 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 2015, Tasmania had the oldest median age of all the states and territories (42 years), followed by South Australia (40 years). The Northern Territory had the youngest median age (32 years), followed by the Australian Capital Territory (35 years).

AGEING POPULATION

Over the next several decades, population ageing is projected to have 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 proportionally larger increase in those aged 65 and over.

Between 1995 and 2015, the proportion of Australia's population aged 15-64 years remained fairly stable, decreasing from 66.6% to 66.2% of the total population. During the same period, the proportion of people aged 65 years and over increased from 11.9% to 15.0% and the proportion of people aged 85 years and over almost doubled from 1.1% of the total population in 1995 to 2% in 2015. Conversely, the proportion aged under 15 years decreased from 21.5% to 18.8%.

CHILDREN (AGED 0-14 YEARS)

In the 20 years between 1995 and 2015, the proportion of children (aged 0-14 years) decreased from 21.5% to 18.8% of the total population.

In the 12 months to 30 June 2015, the total number of children aged 0-14 years in the population increased by 1.1% (47,800 people) compared to an increase of 1.3% (57,000 people) in the previous year ending 30 June 2014. Over this period, the number of 0-4 year olds increased by 7,200 (0.5%), 5-9 year olds increased by 28,200 (1.9%), and those aged between 10-14 years increased by 12,500 (0.9%).

In the year ended 30 June 2015, the Australian Capital Territory recorded the largest percentage increase in the number of children aged 0-14 years (2.4%), followed by Western Australia (1.5%). In contrast, Tasmania recorded a decrease of 0.5%.


WORKING-AGE POPULATION (AGED 15-64 YEARS)

At 30 June 1995, the proportion of the population aged between 15 and 64 years (traditionally referred to as the 'working-age population') was 66.6%. This proportion increased to a high of 67.5% in 2009, before declining to 66.2% by 30 June 2015.

In the 12 months to 30 June 2015, the number of people in the working ages increased by 1.0% (or 152,800 persons). At the state and territory level, Victoria and New South Wales experienced growth rates for this group that were higher than the 1.0% national average at 1.5% and 1.1% respectively. In contrast, Tasmania and the Northern Territory recorded a decrease in the number of 15-64 year olds of 0.2% and less than 0.1% respectively.

There were 286,000 young people aged 15 who entered the working-age population while 240,400 people turned 65 years and left the working-age population in the year ended 30 June 2015.

Comparing the working-age population (aged 15-64 years) with the remainder of the population (aged 0-14 and 65 and greater) over the 20 years to 30 June 2015, the non working-age population is growing faster at 1.5% compared with 1.4% for the working-age population. This faster growth in the non working-ages has been evident since 2010. Over the 5 years to 30 June 2015 the non working-age population has been growing at 2.3% compared with 1.2% for the working-age population. The main contributor to the increased growth of the non working-age population is growth in the population aged 65 and over.


PEOPLE AGED 65 YEARS AND OVER

Over the 20 years between 1995 and 2015, the proportion of the population aged 65 years and over increased from 11.9% to 15.0%. 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 four cohorts have reached 65 and there are 14 remaining.

Notably the past 20 years has seen the proportion of the Northern Territory's population 65 years and over increase from 3.0% to 6.9% due, in part to an increasing life expectancy in the Northern Territory's population.

In the 12 months to 30 June 2015, the number of people aged 65 years and over increased by 116,500 people, representing a 3.4% increase.

All states and territories experienced growth in people aged 65 years and over in the year ended 30 June 2015. The largest increase in this group was in the Northern Territory (5.9%), followed by the Australian Capital Territory (4.7%), Western Australia and Queensland (both 4%).


PEOPLE AGED 85 YEARS AND OVER

Over the past two decades, the number of persons aged 85 years and over increased by 148%, compared with a total population growth of 32.1% over the same period.

In the year ending 30 June 2015, the number of people aged 85 years and over increased by 17,900 people (3.9%) to reach 472,100. There were almost twice as many females (299,100) as males (173,000) 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 (9.6%), followed by Western Australia (5.0%), Victoria (4.5%), Australian Capital Territory (4.2%), Queensland (4.1%), New South Wales (3.5%), Tasmania (3.0%) and South Australia (2.7%).


PEOPLE AGED 100 YEARS AND OVER

Over the past two decades, the number of centenarians increased by 254%, reflecting an increase in life expectancy for both males and females during the period.

In the 12 months to 30 June 2015, the number of centenarians increased by 550 people (14.3%) to reach 4,400. There were more than three times as many females (3,400) as males (1,000) in this age group which reflects the higher life expectancy for females.


SEX RATIOS

The sex ratio relates to the number of males per 100 females in a population or sub-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. Net 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 2015, the sex ratio of the total population for Australia was 99 males per 100 females. At age 0, the sex ratio for Australia at 30 June 2015 was 105.5 males per 100 females. The excess of males at younger ages contrasts with the opposite situation in the older ages, and is attributed to female longevity.

At 30 June 2015, the Northern Territory and Western Australia had 112.2 and 102.1 males per 100 females respectively. All other states and territories had lower ratios of males to females. Victoria and South Australia had 97.8 and 98.2 males per 100 females respectively.

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, Greece, Sweden, Canada 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 2030. For more information, see Population Projections, Australia, 2012 (base) to 2101 (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 to increase by 0.2 percentage points between 2015 and 2020, from 18.8% to 19%, while the proportion of people aged 15-64 years is projected to decrease by 1.3 percentage points, from 66.2% to 64.9%. The proportion of people aged 65 years and over is projected to increase by 1.1 percentage points, from 15% to 16.1%.

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 - at 30 June(a)(b)
	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	18.8	66.2	15.0	37.4	19.0	64.9	16.1	37.7	1.9	83.0
Canada	16.0	67.9	16.1	40.6	16.2	65.5	18.3	41.4	1.6	82.6
China (excl. SARs and Taiwan)	17.2	73.2	9.6	37.0	17.1	70.8	12.1	38.7	1.6	76.5
France	18.5	62.4	19.1	41.2	18.0	61.2	20.8	41.9	2.0	82.8
Greece	14.6	64.0	21.4	43.6	13.9	63.8	22.3	45.4	1.3	81.6
Hong Kong (SAR of China)	12.0	73.0	15.1	43.2	13.1	68.7	18.2	45.1	1.3	84.5
India	28.8	65.6	5.6	26.6	26.8	66.6	6.5	28.1	2.3	69.1
Indonesia	27.7	67.1	5.2	28.4	26.3	67.9	5.9	29.4	2.4	69.5
Italy	13.7	63.9	22.4	45.9	13.2	62.8	24.0	47.8	1.5	83.8
Japan	12.9	60.8	26.3	46.5	12.6	58.9	28.5	48.3	1.5	84.1
Korea (South)	14.0	72.9	13.1	40.6	13.4	70.8	15.8	43.1	1.3	82.8
Malaysia	24.5	69.6	5.9	28.5	22.9	70.1	7.0	30.6	1.9	75.3
New Zealand	20.2	64.9	14.9	38.0	19.7	63.6	16.7	38.6	2.0	82.4
Papua New Guinea	37.1	59.8	3.0	21.2	35.3	61.3	3.4	22.2	3.6	63.2
Philippines	31.9	63.5	4.6	24.2	30.8	64.1	5.1	25.4	2.9	68.7
Singapore	15.5	72.8	11.7	40.0	14.3	70.6	15.1	42.5	1.3	83.7
South Africa	29.2	65.7	5.0	25.7	28.4	66.2	5.5	26.9	2.3	57.7
Sweden	17.3	62.8	19.9	41.0	18.0	61.3	20.7	41.2	1.9	82.8
United Kingdom	17.8	64.5	17.8	40.0	18.3	63.3	18.4	40.4	1.9	81.2
United States of America	19.0	66.3	14.8	38.0	18.6	64.7	16.7	38.6	1.9	79.6
Viet Nam	23.1	70.2	6.7	30.4	22.9	69.0	8.0	32.6	2.0	76.3
World	26.1	65.7	8.3	29.6	25.5	65.2	9.3	30.9	2.5	71.7
(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.
Source: 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 (2015) World Population Prospects: The 2015 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 2012 (base) to 2101 (cat. no. 3222.0).