Based on the Australian Bureau of Statistics estimated resident populations. Population projections based on data from the NSW Department of Planning and Environment (SAPHaRI). Centre for Epidemiology and Evidence, NSW Ministry of Health.
Population estimates as at 30 June each year. Components may not add up to the total exactly and population estimates may not be the same as other publications, due to rounding.Local Health District population projections based on pre-2016 Census Estimated Resident Populations have been used in this report (see methods tab for more detail).
Population estimates as at 30 June were used for calendar years, while estimates as at 31 December were used for financial years.
Age- and sex-specific estimated resident populations (ERPs) for NSW Statistical Areas (Levels 1 and 2) (SA1 and SA2) at 30 June were obtained from the Australian Bureau of Statistics (ABS) for use with calendar year data. Linear temporal interpolation was used to derive 31 December age- and sex-specific population estimates for use with financial year data. Populations of NSW Local Health Districts (LHDs) were derived by aggregating the appropriate SA1-level ERPs based on an SA1 to LHD concordance mapping.
Population estimates match the year of health data. For example, the rate of NSW residents hospitalised in, for example, 2017-18 is calculated using the number of hospitalisations in 2017-18 and the estimate of residential population in NSW in the 2017-18 financial year. Further, the death rate of NSW residents in, for example, 2017 is calculated using the number of deaths in 2017 and the estimate of residential population in NSW in the 2017 calendar year.
The 2001 Australian standard population was used for age-adjustment or standardisation of rates. For this report, the Australian estimated residential population (persons) as at 30 June 2001 was used as the standard population. The same population was used for males and females to allow valid comparison of age-standardised rates between the sexes. This standard population is determined by the Australian Institute of Health and Welfare and is changed every 20 years.
Age-adjustment of rates used direct age-standardisation. This method adjusts for effects of differences in the age composition of populations across time or geographic regions. The directly age-standardised rate is the weighted sum of age-specific (five-year age group) rates, where the weighting factor is the corresponding age-specific standard population. Please refer to the HealthStats PLUS Methods paper on Age standardisation.
The projections have been produced by the NSW Department of Planning, Industry and Environment (DPIE). The projections result from assumptions about future trends in fertility, mortality and migration and incorporate information from DPIE, the ABS, the Commonwealth Department of Immigration and Border Control and the NSW Ministry of Health. The projections used in HealthStats NSW are based on the latest estimated resident population as published by the ABS linearly interpolated to the first projection year in the DPIE estimates following this time point.
The inter-census year projections to 2036 have been produced by the Centre for Epidemiology and Evidence by interpolating the census-year (2016, 2021, 2026, 2031 and 2036) projections provided by Department of Planning, Industry and Environment. These projections have been used to calculate rates in indicators showing projected deaths and hospitalisations in NSW.
The year-to-year projections of population to 2036 by 5-year age group for the whole of New South Wales and Local Health Districts are available from HealthStats NSW. Population projections for LGAs in NSW are also available for the following age groups: 0-14, 15-44, 45-64 and 65 years and over, for the years 2016, 2021, 2026, 2031 and 2036.
NSW population, household and dwelling projections. NSW Department of Planning, Industry and Environment. Available at: http://www.planning.nsw.gov.au/Research-and-Demography/Demography/Population-Projections
Projections of numbers and rates of deaths, hospitalisations or incidence are based on the assumption that past trends will continue into the future. Projections are helpful in high-level planning and resource allocation, however the reliability of the projected estimates decreases over time from the year in which the forecasts are based.
The base data used for hospitalisations was from 1 July 2001 onwards. For deaths data, the last 20 years were used as the base data for predictions. In all cases, it was assumed that current trends will continue. No allowance was made for the impact of future injury prevention programs or injury treatment regimens.
For each sex and age group combination, the number of future events (deaths, hospitalisations or cases) was estimated by fitting a generalised linear model with events as a linear function of year. A Poisson distribution was assumed for the events. The model was fitted using a log link function and the log of the estimated residential population as an offset variable, using the Genmod procedure in SAS Enterprise Guide 7.15 (SAS Institute 2017). The projected counts for each age group were used to calculate projected age-standardised rates, and combined to calculate total counts for males, females and persons.
In HealthStats NSW, the total population used when calculating age-standardised rates are the Estimated Resident Populations produced by the Australian Bureau of Statistics (ABS) and projections produced by the NSW Department of Planning, Industry and Environment (DPIE).
The projected population estimates result from assumptions about future trends in fertility, mortality and migration and incorporate information from DPIE, the ABS, the Commonwealth Department of Immigration and Border Control and the NSW Ministry of Health. The projected population estimates used in HealthStats NSW are based on the latest Estimated Resident Population as published by the ABS linearly interpolated to the first projection year in the DPIE estimates following this time point. Population estimates from 2018 onwards incorporate DPIE projections.
NSW Department of Planning, Industry and Environment. New South Wales State and Local Government Area Population Projections. Available at: https://www.planning.nsw.gov.au/Research-and-Demography/Population-projections/Projections
SAS Institute. SAS Enterprise Guide version 7.15. Cary, NC: SAS Institute, 2017. Available at: https://www.sas.com/en_au/software/enterprise-guide.html
Local Health Districts (LHDs) are health administrative areas constituted under Section 17 of the NSW Health Services Act 1997 which became effective from January 2011 and were initially called Local Health Networks.
There are 15 geographically-based LHDs (eight covering the Sydney metropolitan region and seven covering rural and regional NSW) and two specialist networks focusing on Children's and Paediatric Services and Forensic Mental Health. A third network operates across the public health services provided by three Sydney facilities operated by St Vincent's Health: these include St Vincent's Hospital and the Sacred Heart Hospice at Darlinghurst and St Joseph’s at Auburn.
LHDs replaced the former Area Health Services. Each LHD has its own budget, management and accountabilities. Geographically-based LHDs are overseen by Governing Boards. Please refer to the NSW Health website for a list of Local Health Districts and the membership of Boards.
Local Health Districts are:
Metropolitan NSW: Central Coast, Illawarra Shoalhaven, Nepean Blue Mountains, Northern Sydney, South Eastern Sydney, South Western Sydney, Sydney, Western Sydney.
Rural & regional NSW: Far West, Hunter New England, Mid North Coast, Murrumbidgee, Northern NSW, Southern NSW, Western NSW.
The term ‘small area’ refers to a sub-state geographical area with a small population. Data analysed for small areas may result in estimates that display considerable variability from year to year, particularly for rare conditions or events. Smoothing is a general term for statistical methods used to reduce the random variability of data in small populations. Examples of smoothing include rounding, moving averages, extending the period of time in which cases are counted or increasing the size of the areas. In addition, statistical smoothing can be used to adjust raw estimates in small areas by taking into account information from adjacent areas (local or spatial variability) and from the whole state (global or non-spatial variability).
In HealthStats NSW, the most frequently used smoothing technique for data presented by Local Health District is the aggregation of several years of data together followed by the calculation of a rolling average across the aggregated years. For some indicators, data for particular Local Health Districts may be suppressed due to very low numbers and privacy concerns. Please refer to Notes under the graphs or Methods tabs for confirmation of suppression and the smoothing technique used.
In HealthStats NSW, the total population used for each Local Health District when calculating age-standardised rates are the Estimated Resident Populations produced by the Australian Bureau of Statistics (ABS) and projections produced by the NSW Department of Planning, Industry, and Environment. As sub-state projections based on the 2016 Census are not yet available, population projections for Local Health Districts (estimated population for 2017 and onwards) are based on Estimated Resident Populations produced by the ABS prior to the 2016 Census.
NSW Health. Local Health Districts and specialty networks. Available at https://www.health.nsw.gov.au/lhd/Pages/default.aspx
The five yearly Census of Population and Housing is the primary source of basic population statistics, providing a total count of the population on Census night.
The Census is the primary source of basic population statistics, providing a total count of the population on census night. Population counts can be provided according to place of enumeration or according to place of usual residence. In Australia the key population measure is the estimated resident population (ERP), which is based on the concept of a person’s ‘usual residence’ for a period of 12 months or more within Australia. The ERP in a census year is derived from the census count, with adjustments for estimated undercount and for Australian residents temporarily overseas on census night. Between censuses the ERP is updated using information on birth and death registrations from state and territory Registrars of Births, Deaths and Marriages, and overseas arrivals and departures data from the Department of Immigration and Border Protection, as well as Medicare registration changes of address for modelling interstate migration.
Population estimates are referred to as preliminary, revised or final. Preliminary estimates are generally made available five to six months after the reference period. Revised estimates are generally published each September for the financial year ending in the previous year. Final estimates are published for the previous intercensal period after each census.
Preliminary estimates can be obtained from the Australian Bureau of Statistics publication: Regional population growth, Australia, published annually in March and containing estimates for the previous year (ABS 3218.0).
Estimated resident populations (i.e. data to 30 June 2015) for the new Local Government Areas (LGAs) established in 2016 in NSW were calculated by the Centre for Epidemiology and Evidence, NSW Ministry of Health, based on ABS data from historical LGA, Statistical Local Area (SLA), census collection district (CD) or SA1-level ERPs.
The projections for 2016, 2021, 2026, 2031 and 2036 have been produced by the NSW Department of Planning, Industry and Environment using the cohort component modelling method. The model takes a population broken down by age groups and moves them forward in time using assumptions about when and how many people will die, how many babies women will have at certain ages, and how many people will move into and out of an area. This is the most common method used by demographers. The details of the method, process and assumptions can be found on the NSW Department of Planning, Industry and Environment website.
The year-to-year projections to 2036 have been produced by the Centre for Epidemiology and Evidence, NSW Ministry of Health using as data points, the projections produced by the NSW Department of Planning, Industry and Environment. These projections have been used to calculate rates in indicators showing projected deaths and hospitalisations in NSW.
The year-to-year projections of population to 2036 by 5-year age group for the whole of New South Wales, Local Health Districts and Primary Health Networks are available in HealthStats NSW. Population projections for LGAs are also available for the following age groups: 0-14, 15-44, 45-64 and 65 years and over, for the years 2016, 2021, 2026, 2031 and 2036. Projections by 5-year age group are available for some LGAs from the NSW Department of Planning, Industry and Environment website. Projections of population by sex are not available for Local Government Areas.
The NSW population projections use a top-down approach working down from the state, to region, to local government area (LGA). State and region projections have not been affected by changes to the LGA boundaries. LGA projections for the new boundaries have been created by adding together projections where whole Councils have been amalgamated. Where boundaries have been changed to create new Councils, populations were distributed based on information about housing completions and short-term housing supply forecasts.
The 2016 projections are for new Councils that have been announced. Data for new Councils that are pending will be released when they become official (please see NSW Department of Planning, Industry and Environment, NSW Population Projection User Guide below).
Population data is often presented in a form of a pyramid. A population pyramid consists of two back-to-back bar graphs, one showing the number of males and one showing the number of females in a particular population in five-year age groups.
Population pyramids provide an overall picture of the age and sex structure in a population. Age and sex are important determinants of the health of individuals. Thus, the age and sex structure of a population has a strong effect on patterns of illness and use of health services.
The shape of a pyramid quickly communicates the details of the population. Population pyramids that are triangular (broad at the base and narrow rapidly towards the top) indicate a large number of children and a small number of older people, which implies a high fertility rate, high death rate, and short life expectancy. A more rectangular shape reflects lower death rates, with most of the population living to old age. Migration patterns, for example young adults moving to urban areas and retired people moving to coastal areas, also affect the shape of the population pyramid. Changes in the shape of a population pyramid over time reflect the changing composition of the population, associated with changes in fertility, mortality and migration at each age.
Australian Bureau of Statistics. Regional population growth, Australia. 3218.0. Canberra: ABS. Available at: http://www.abs.gov.au/AUSSTATS/abs@.nsf/mf/3218.0
Australian Bureau of Statistics. Australian Historical Population Statistics, 2014. Catalogue no. 3105.0.65.001. Canberra: ABS, 2008. Available at: http://www.abs.gov.au/ausstats/abs@.nsf/PrimaryMainFeatures/3105.0.65.001?OpenDocument
Department of Planning, Industry and Environment. New South Wales State and Local Government Area Population Projections. Available at: http://www.planning.nsw.gov.au/en-au/deliveringhomes/populationandhouseholdprojections/data.aspx
Note from the NSW Department of Planning, Industry and Environment website. Available at: https://www.planning.nsw.gov.au/Research-and-Demography/Demography/Population-projections/NSW-Population-Projections-User-Guide
• The estimated residential population of NSW in 2017 was 7,861,068 which was just under one-third of Australia's population. The population of NSW in 2036 is projected to be approximately 9,925,548.
• In 2017 the female population slightly outnumbered the male population (98.2 males per 100 females) and this gap is predicted to remain similar in 2036 (98.4 males per 100 females).
• The proportion of females in the population increases with age. In 2017 females made up 50.4% of the total population but 53.3% of the NSW population aged 65 years or more, and 62.4% of the population aged 85 years or more.
• The NSW population is predominantly urban. In 2016 approximately 75.0% of the NSW population lived in major cities, 18.8% lived in inner regional areas, and 6.2% in outer regional and remote areas.
• In 2017 approximately 3.0% of the total population in NSW were Aboriginal and were relatively younger overall than the non-Aboriginal population. Of the total Aboriginal population in 2017, 11.8% were aged 0-4 years, compared with 6.1% of the non-Aboriginal population, and 0.2% were aged 85 years and over, compared with 2.2% of the non-Aboriginal population.
Demography is the study of populations, especially with reference to size and density, fertility, mortality, growth, age and sex distribution, migration and vital statistics and the interaction of all these with social and economic conditions.
Understanding population trends informs decision-making in planning, allocating and providing a wide variety of services, including population and community health, primary health, specialist and hospital services.
Age and sex are important determinants of the health of individuals. Thus, the age and sex structure of a population has a strong effect on patterns of illness and use of health services.
The age and sex structure will vary among different regions, for reasons such as young adults moving to cities for study or work and older people retiring to coastal areas.
A dictionary of epidemiology. Fifth edition. Oxford reference. http://www.oxfordreference.com/view/10.1093/acref/9780195314496.001.0001/acref-9780195314496
NSW Department of Planning and Environment. Demography. http://www.planning.nsw.gov.au/Research-and-Demography/Demography
NSW Department of Planning and Environment at http://www.planning.nsw.gov.au/Research-and-Demography/Demography
Australian Bureau of Statistics at http://www.abs.gov.au
Australian Institute of Health and Welfare at http://www.aihw.gov.au
healthdirect at http://www.healthdirect.gov.au