3228.0.55.001 - Population Estimates: Concepts, Sources and Methods, 2009
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 12/06/2009
Page tools:
 Print Page
 Print All
| ||
|
GLOSSARY
Demographic statistics are based on this definition. Age specific An age specific rate is a measure relating to the experience of each age group. For example, age-specific fertility rates are usually expressed in terms of the experience of females within each of the five-year age groups (15-19 years, 20-24 years, 25-29 years, etc.), or they can also be expressed in terms of single age rates. Age-specific death rates Age-specific death rates are the number of deaths (occurred or registered) during the calendar year at a specified age per 1,000 of the estimated resident population of the same age at the mid-point of that year (30 June). Pro rata adjustment is made in respect of deaths for which the age of the deceased is not given. Age-specific fertility rates Age-specific fertility rates are the number of live births (occurred or registered) during the calendar year, according to the age of the mother, per 1,000 of the female estimated resident population of the same age at 30 June. For calculating these rates, births to mothers under 15 years are included in the 15-19 age group, and births to mothers aged 50 years and over are included in the 45-49 age group. Pro rata adjustment is made for births for which the age of the mother is not given. At risk population The population at risk of experiencing a particular event. For example, the at risk population for calculating divorce rates is the married population. Australian resident For estimated resident population statistics, the Census year population estimates classify a person as an Australian resident if the person has (in the most recent Census) reported a usual address in Australia where the person has lived or intends to live for six months or more in the Census year. The post-censal estimates, while based on the Census data, are updated with international migration data that have a criterion of one year or more of intended stay in or departure from Australia. For overseas arrivals and departures statistics, Australian residency is self-reported by travellers when completing an Incoming or Outgoing Passenger Card. Average annual growth rate The average annual growth rate, r, is calculated as a percentage using the formula: where: Balance of state or territory The aggregation of all statistical divisions (SDs) within a state or territory other than its capital city SD. See major statistical region in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Birth The delivery of a child, irrespective of the duration of pregnancy, who, after being born, breathes or shows any evidence of life such as heartbeat. Capital city Refers to the capital city statistical divisions (SDs) of states and territories as defined in Statistical Geography: Volume 1 - Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Category jumping Category jumping was the term used to describe changes between stated intention and actual duration of stay of travellers to/from Australia, such that their classification as short-term or as long-term/permanent movers is different at arrival/departure from that after twelve months. For more information, see Migration, Australia, 2002-03 (cat. no. 3412.0), chapter 6, 'Special article: Adjustments to overseas migration estimates'. The Australian resident component of category jumping for a reference quarter was estimated by comparing the number of residents departing short-term in that quarter with all residents who left in that quarter and return in the following 12 months, to obtain the net number of Australian residents who 'jumped category'. Similarly, the number of overseas visitors arriving short-term in a quarter was compared with all overseas visitors who arrived in that quarter and depart in the following 12 months, to obtain the net number of overseas visitors 'who jumped category'. Estimates of category jumping were derived by subtracting the Australian resident component from the overseas visitor component. Category jumping is no longer used following the implementation of the NOM 12/16 month rule. Category of movement Overseas arrivals and departures are classified according to length of stay (in Australia or overseas), recorded in months and days by travellers on passenger cards. There are three main categories of movement:
A significant number of travellers (i.e. overseas visitors to Australia on arrival and Australian residents going abroad) state exactly 12 months or one year as their intended period of stay. Many of them stay for less than that period and on their departure from, or return to, Australia are therefore classified as short-term. Accordingly, in an attempt to maintain consistency between arrivals and departures, movements of travellers who report their actual or intended period of stay as being one year exactly are randomly allocated to long-term or short-term in proportion to the number of movements of travellers who report their actual length of stay as up to one month more, or one month less, than one year. Census The complete enumeration of a population or groups at a point in time with respect to well-defined characteristics (e.g. Population, Manufacturing, etc.). When the word is capitalised, "Census" usually refers to the national Census of Population and Housing. Census collection district (CD) The smallest geographic area for which population estimates are calculated. For more information see the Statistical Geography: Volume 1 - Australian Standard Geographical Classification (ASGC) (cat.no.1216.0). Census count The Census of Population and Housing enumerates persons on the basis of where they were located on Census Night. The Census also compiles information on people according to their place of usual residence. This information is coded to Census collection districts (CDs). This means that Census counts of people can be produced according to their location on Census Night as well as their place of usual residence. Characteristics of households are based on persons usually resident in a dwelling. Census Post Enumeration Survey (PES) The Census Post Enumeration Survey (PES) is a household survey conducted shortly after the Census. The PES allows the ABS to estimate the number of people missed in the Census and the number counted more than once. Usually more people are missed than counted more than once in Australia, resulting in a net undercount. Results from the PES contribute to a more accurate calculation of the estimated resident population (ERP) for Australia and the states and territories which is then backdated to 30 June of the Census year. Confinement A pregnancy which results in at least one live birth. Country of birth The classification of countries is the Standard Australian Classification of Countries (SACC). For more detailed information refer to Standard Australian Classification of Countries (SACC) (cat. no. 1269.0) and Migration, Australia (cat. no. 3412.0). Country of residence Country of residence refers to the country in which travellers regard themselves as living or as last having lived. Death Death is the permanent disappearance of all evidence of life after birth has taken place. The definition excludes deaths prior to live birth. For the purposes of the Deaths and Causes of Deaths collections conducted by the ABS, a death refers to any death which occurs in, or en route to Australia and is registered with a state or territory Registry of Births, Deaths and Marriages. Divorce Dissolution of marriage through a decree absolute from the Family Court. Dwelling A dwelling is a building or structure in which people live. This can be a house, a block of flats, a caravan or tent, humpy or park bench. For the purposes of Census of Population and Housing, dwellings are classified into private and non-private dwellings. Each of these dwelling types is further divided into occupied and unoccupied dwelling categories. Estimated resident population (ERP) The official measure of the population of Australia is based on the concept of residence. It refers to all people, regardless of nationality or citizenship, who usually live in Australia, with the exception of foreign diplomatic personnel and their families. It includes usual residents who are overseas for less than 12 out of 16 months. It excludes overseas visitors who are in Australia for less than 12 out of 16 months. Exnuptial birth An exnuptial birth is the birth of a child whose parents are not legally married to each other at the time of the child's birth. Family A family is defined by the ABS as: two or more persons, one of whom is at least 15 years of age, who are related by blood, marriage (registered or de facto), adoption, step or fostering, and who are usually resident in the same household. The basis of a family is formed by identifying the presence of either a couple relationship, lone parent-child relationship or other blood relationship. Some households will, therefore, contain more than one family. Group household A group household is a household consisting of two or more unrelated people where all persons are aged 15 years or over. There are no reported couple relationships, parent-child relationships or other blood relationships in these households. Household A household is a group of two or more related or unrelated people who usually reside in the same dwelling, who regard themselves as a household and who make common provision for food or other essentials for living; or a person living in a dwelling who makes provision for his or her own food and other essentials for living, without combining with any other person. Households include group households of unrelated persons, same-sex couple households, single-parent households as well as one-person households. A household may consist of:
A household usually resides in a private dwelling (including caravans etc. in caravan parks). Persons usually resident in non-private dwellings, such as hotels, motels, boarding houses, jails and hospitals, are not included in household estimates. Household estimate Household estimate is a measure of the number of households of the usually resident population. It is based on the Census count of households which is adjusted for missed households, households of overseas visitors, households of Australian residents where all members were temporarily overseas at the time of the Census and households of Australian residents where all members were not home on Census Night and spent Census Night in a non-private dwelling in Australia. Indigenous birth The birth of a live-born child where either the mother or the father was identified as being of Aboriginal or Torres Strait Islander origin on the birth registration form. Indigenous births in Indigenous population estimates/projections are those which result by applying assumed age-specific fertility rates to Aboriginal and Torres Strait Islander mothers in reproductive ages. Indigenous death The death of a person who is identified as being of Aboriginal or Torres Strait Islander origin on the death information form. Indigenous origin Persons who identify as being of Aboriginal or Torres Strait Islander origin. Indigenous status See Indigenous origin. Intended length of stay On arrival in Australia, all overseas visitors are asked to state their 'Intended length of stay in Australia'. On departure from Australia, all Australian residents are asked to state their 'Intended length of stay overseas'. Intercensal discrepancy Intercensal discrepancy is the difference between two estimates at 30 June of a Census year population, the first based on the latest Census and the second arrived at by updating the 30 June estimate of the previous Census year with intercensal components of population change which take account of information available from the latest Census. It is caused by errors in the start and/or finish population estimates and/or in estimates of births, deaths or migration in the intervening period which cannot be attributed to a particular source. Intercensal error Intercensal error is the difference between two estimates at 30 June of a Census year population, the first based on the latest Census and the second arrived at by updating the 30 June estimate of the previous Census year with intercensal components of population change which do not take account of information available from the latest Census. Internal migration The difference between the number of persons who have changed their place of usual residence by moving into a defined geographical area within Australia and the number who have changed their place of usual residence by moving out of that defined geographical area during a specified time period. This difference may be either positive or negative. Interstate migration See net interstate migration. Life table A life table is a statistical model used to represent mortality of a population. In its simplest form, a life table is generated from age-specific death rates and the resulting values are used to measure mortality, survivorship and life expectancy. Local government area (LGA) Local government areas (LGAs) are the spatial units which represent the geographical areas of incorporated local government councils and incorporated Community Government Councils (CGCs) where the CGC is of sufficient size and statistical significance. The various types of LGAs are cities (C), areas (A), rural cities (RC), towns (T), shires (S), district councils (DC) and municipalities (M). Further information concerning LGAs is contained in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Long-term arrivals Long-term arrivals comprise:
Long-term departures Long-term departures comprise:
Main destination Australian residents travelling overseas are asked on departure for the name of the country in which they intend to spend most time. Main state/territory of stay Overseas visitors are asked on departure for the name of the state or territory in which they spent the most time. Marital status Two separate concepts are measured by the Australian Bureau of Statistics. These are registered marital status and social marital status. Registered marital status refers to formally registered marriages and divorces. Registered marital status is a person's relationship status in terms of whether he or she has, or has had, a registered marriage with another person. Accordingly, people are classified as either 'never married', 'married', widowed' or 'divorced. Social marital status is the relationship status of an individual with reference to another person who is usually resident in the household. A marriage exists when two people live together as husband and wife, or partners, regardless of whether the marriage is formalised through registration. Individuals are, therefore, regarded as married if they are in a de facto marriage, or if they are living with the person to whom they are registered as married. Under social marital status, a person is classified as either 'married' or 'not married' with further disaggregation of 'married' to distinguish 'registered married' from 'de facto married' person. All references to marital status in this publication refer to registered marital status. Marriage Refers to registered marriages only. Under the Australian Marriage Act 1961 (Cwlth), a marriage may be celebrated by a minister of religion registered as an authorised celebrant, by a district registrar or by other persons authorised by the Attorney-General. Notice of the intended marriage must be given to the celebrant at least one calendar month but within six calendar months before the marriage. A celebrant must transmit an official certificate of the marriage for registration in the state or territory in which the marriage took place. Migration adjustment The ABS applies a number of adjustments to overseas arrivals and departures data in order to produce estimates of net overseas migration (NOM). These mainly comprise adjustments designed to reflect differences between stated travel intentions and actual travel behaviour, but (in the case of revised NOM estimates) also include adjustments to transform numbers of overseas movements into numbers of travellers. Migration adjustments replaced the 'category jumping' adjustments previously applied to NOM estimates. Mortality Experience of death in a population and its measurement. Moving average Average value of a series of data over a fixed period of time such that, as new data become available, the earliest dated observation is removed from the calculation of the average and the most recent observation added in its place. For example, a 3 term moving average is used to smooth input components to calculate expansion factors for interstate migration. Natural increase Excess of births over deaths. Net interstate migration (NIM) The difference between the number of persons who have changed their place of usual residence by moving into a given state or territory and the number who have changed their place of usual residence by moving out of that state or territory. This difference can be either positive or negative. Net overseas migration (NOM) Net overseas migration is the net gain or loss of population through immigration to Australia and emigration from Australia. It is:
When using the current method for estimating final net overseas migration this term is then based on a travellers' actual duration of stay or absence using the 12/16 rule. Preliminary NOM estimates are modelled on patterns of traveller behaviours observed in final NOM estimates for the same period two years earlier. Net permanent and long-term movement The difference between the number of permanent (settler) and long-term arrivals and the number of permanent and long-term departures. Short-term movements are excluded. Net population growth For Australia, net population growth is the sum of natural increase and net overseas migration. For the states and territories, net population growth also includes net interstate migration. Net undercount The difference between the actual Census count (including imputations) and an estimate of the number of people who should have been counted in the Census. This estimate is based on the PES conducted after each Census. For a category of person (e.g. based on age, sex and state of usual residence), net undercount is the resultant of Census undercount, overcount, misclassification and imputation error. NOM arrivals NOM arrivals are all overseas arrivals that contribute to net overseas migration (NOM). It is the number of incoming international travellers who stay in Australia for 12 months or more and are added to the population. When using the current method for estimating net overseas migration this term is then based on a travellers' actual duration of stay using the 12/16 rule. NOM departures NOM departures are all overseas departures that contribute to net overseas migration (NOM). It is the number of outgoing international travellers (Australian residents and long term visitors to Australia) who leave Australia for 12 months or more and are subtracted from the population. When using the current method for estimating net overseas migration this term is then based on a travellers' actual duration of absence using the 12/16 rule. Non-private dwelling (NPD) Non-private dwellings (NPDs) are residential dwellings with accommodation which are not included in the Census of Population and Housing list of private dwelling categories. NPDs are classified according to their function. They include hotels, motels, guest houses, jails, religious and charitable institutions, military establishments, hospitals and other communal dwellings. Where this type of accommodation includes self-contained units (as provided by hotels, motels, homes for the elderly and guest houses), the units are enumerated as part of the NPD. Complexes such as retirement villages, which have a combination of self-contained units, hostel and/or nursing home accommodation, are enumerated as NPDs. Nuptial birth A nuptial birth is the birth of a child born of parents who are legally married at the time of the child's birth. Nuptiality Nuptiality relates to the registered marital status of persons and the events such as marriages, divorces and widowhood. Confinements and births are identified as being nuptial where the father registered was married to the mother at the time of birth, or where the husband died during pregnancy. Confinements and children of Indigenous mothers considered to be tribally married are classified as nuptial. Other confinements, and the children resulting from them, are classified as ex-nuptial whether or not both parents were living together at the time of birth. Occupied private dwelling (OPD) An occupied private dwelling is defined as the premises occupied by a household on Census Night (see Household). Overseas arrivals and departures (OAD) Overseas arrivals and departures (OAD) refer to the arrival or departure of persons, through Australian airports (or sea ports), which have been recorded. Statistics on OAD relate to the number of movements of travellers rather than the number of travellers (i.e. the multiple movements of individual persons during a given reference period are all counted). Overseas migration See net overseas migration (NOM). Overseas migration adjustment See Migration adjustment. Partner A person in a couple relationship with another person usually resident in the same household. The couple relationship may be in either a registered or de facto marriage, and includes same-sex couples. Permanent arrivals Permanent arrivals (settlers) comprise:
This definition of settlers is used by the Department of Immigration and Citizenship (DIAC). Prior to 1985 the definition of settlers used by the ABS was the stated intention of the traveller only. Numerically the effect of the change in definition is insignificant. The change was made to avoid the confusion caused by minor differences between data on settlers published separately by the ABS and DIAC. Permanent departures Permanent departures are Australian residents (including former settlers) who on departure state that they are departing permanently. Population age-sex pyramid A population age-sex pyramid is a bar chart graphically representing the age structure of the population, usually in five-year age groups, for males and females separately. The age structure of the population usually approximates the shape of a pyramid because mortality progressively reduces the number in each birth cohort as it ages. The age pyramid is useful to show the existence of unusually large or small cohorts, and in this way, not only conveys a lot about a country's past demographic history, but also a great deal about its demographic future. Population growth For Australia, population growth is the sum of natural increase and net overseas migration. For states and territories, population growth also includes net interstate migration. After the Census, intercensal population growth also includes an allowance for intercensal discrepancy. Private dwelling (PD) A private dwelling in the Census is defined as a house, flat, part of a house, or even a room; but can also be a house attached to, or rooms above shops or offices; an occupied caravan in a caravan park or boat in a marina, a houseboat, or a tent if it is standing on its own block of land. A caravan situated on a residential allotment is also classed as a PD. Residents temporarily overseas (RTOs) Residents temporarily overseas are Australian residents who are overseas on Census Night for a period less than 12 out of 16 months. Sex ratio The sex ratio relates to the number of males per 100 females. The sex ratio is defined for total population, at birth, at death and among age groups by selecting the appropriate numerator and denominator of the ratio. Short-term arrivals Short-term arrivals comprise:
Short-term departures Short-term departures comprise:
State or territory of clearance State or territory of clearance refers to the state or territory in which a passenger is cleared by Customs and Immigration authorities. Embarkation or disembarkation and clearance are usually, but not necessarily, in the same state or territory. State or territory of intended residence State or territory of intended residence is derived from the intended address given by permanent arrivals (settlers), and by Australian residents returning after a journey abroad. Particularly in the case of the former, this information does not necessarily relate to the state or territory in which a traveller will eventually establish a permanent residence. State or territory of intended address/where lived Overseas visitors are asked on arrival in Australia for their state or territory of intended address. On departure from Australia overseas visitors are asked the state or territory where they spent most time. Australian residents are asked on departure for the state or territory in which they live/lived. Residents returning to Australia are asked for their state or territory of intended address. State or territory of intended stay See state or territory of intended addressed/where lived. State or territory of registration State or territory of registration refers to the state or territory in which the event was registered. State or territory and statistical local area (SLA) of usual residence State or territory and statistical local area (SLA) of usual residence refers to the state or territory and SLA of usual residence of:
In the case of overseas movements, state or territory of usual residence refers to the state or territory regarded by the traveller as the one in which he/she lives or has lived. State or territory of intended residence is derived from the intended address given by settlers, and by Australian residents returning after a journey abroad. Particularly in the case of the former, this information does not necessarily relate to the state or territory in which the traveller will eventually establish a permanent residence. Statistical district (S Dist) Statistical districts (S Dist) consist of selected, significant, predominantly urban areas in Australia which are not located within a capital city statistical division (SD). S Dists enable comparable statistics to be produced about these selected urban areas. Further information concerning S Dists is contained in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Statistical division (SD) Statistical divisions (SDs) consist of one or more statistical subdivisions (SSDs). The divisions are designed to be relatively homogeneous regions characterised by identifiable social and economic units within the region, under the unifying influence of one or more major towns or cities. Further information concerning SDs is contained in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Statistical local area (SLA) Statistical local areas (SLAs) are, in most cases, identical with, or have been formed from a division of, whole local government areas (LGAs). In other cases, they represent unincorporated areas. In aggregate, SLAs cover the whole of a state or territory without gaps or overlaps. In some cases legal LGAs overlap statistical subdivision boundaries and therefore comprise two or three SLAs (Part A, Part B and, if necessary, Part C). Further information concerning SLAs is contained in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Statistical subdivision (SSD) Statistical subdivisions (SSDs) are of intermediate size, between statistical local area (SLA) and statistical division (SD). In aggregate, they cover the whole of Australia without gaps or overlaps. They are defined as socially and economically homogeneous regions characterised by identifiable links between the inhabitants. In the non-urban areas an SSD is characterised by identifiable links between the economic units within the region, under the unifying influence of one or more major towns or cities. Further information concerning SSDs is contained in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0). Total fertility rate The sum of age-specific fertility rates. It represents the number of children a female would bear during her lifetime if she experienced current age-specific fertility rates at each age of her reproductive life. Underenumeration See net undercount. Unoccupied private dwellings These are structures built specifically for living purposes which are habitable, but unoccupied at the time of the Census of Population and Housing. Vacant houses, holiday homes, huts, cabins (other than seasonal workers' quarters) and houseboats are counted as unoccupied dwellings. Also included are newly completed dwellings not yet occupied, dwellings which are vacant because they are due for demolition or repair, dwellings to let and dwellings where all members of the household were absent on Census Night. Usual residence Usual residence within Australia refers to that address at which the person has lived or intends to live for a total of six months or more in a given reference year. Year of occurrence Data presented on year of occurrence basis relate to the date the event occurred. Year of registration Data presented on year of registration basis relate to the date the event was registered. Document Selection These documents will be presented in a new window.
|
|