3228.0 - Demographic Estimates and Projections: Concepts, Sources and Methods, 1999

ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 30/08/1999

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Contents >> Glossary

	Aboriginal and Torres Strait Islander origin	The 1996 Census form asked the following question of each person: Demographic statistics are based on this definition.
	Age-specific birth rates	See Age-specific fertility rates.
	Age-specific death rates	Age-specific death rates are the number of deaths registered (or occurred) during the calendar year at a specified age per 1,000 of the estimated resident population of the same age at mid-point of the year (30 June). The infant mortality rate is used for the age-specific death rate for children under one year of age. Pro rata adjustment is made in respect of deaths for which the age of the deceased is not given.
	Age-specific divorce rates	Because of the different purposes to which they are put, two different populations may be used in the calculation of age-specific divorce rates: Per 1,000 population - this relates the number of divorces recorded in the calendar year, by age at decree made absolute, to the estimated resident population of the same age at 30 June. Males under 18 and females under 16 are excluded from the population. Per 1,000 married population - this relates the number of divorces recorded in a calendar year, by age at decree made absolute, to the married population of the same age at 30 June. Those classified as permanently separated are included in the married population. Males and females under 15 are excluded from the population. Wherever used, the definition adopted is indicated.
	Age-specific fertility rates	Age-specific fertility rates are the number of live births registered (or occurred) during the calendar year, according to the age of the mother, per 1,000 of the female resident population of the same age at 30 June. For calculating these rates, births to mothers under 15 are included in the 15–19 age group, and births to mothers aged 50 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.
	Age-specific first marriage rates	Because of the different purposes to which they are put, two different populations may be used in the calculation of age-specific first marriage rates: Per 1,000 population - this relates the number of first time marriages of men or women registered in the calendar year, by age at marriage, to the estimated resident population in the same age at 30 June. Males and females aged under 15 are excluded from the population. Per 1,000 never married population - this relates the number of first time marriages of men or women registered in a calendar year, by age at marriage, to the never married population of men or women of the same age at 30 June. Males and females aged under 15 are excluded from the population. Wherever used, the definition adopted is indicated.
	Age-specific marriage rates	Because of the different purposes to which they are put, two different populations may be used in the calculation of age-specific marriage rates: Per 1,000 population - this relates the number of marriages of men or women registered in a calendar year, by age at marriage, to the estimated resident population in the same age. Males and females aged under 15 are excluded from the population. Per 1,000 not currently married population - this relates the number of marriages of men or women registered in a calendar year, by age at marriage, to the not currently married population of men or women of the same age at 30 June. Males and females aged under 15 are excluded from the population. Wherever used, the definition adopted is indicated.
	Age-specific remarriage rates	Age-specific remarriage rates are the number of remarrying men or women registered in the calendar year, by age at marriage, per 1,000 widowed and divorced estimated resident population of the same sex and age at 30 June. Males and females aged under 15 years are excluded from the 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 1996 Census) reported a usual address in Australia where the person has lived or intends to live for six months or more in 1996. 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. In the 2001 Census, persons who usually live in another country and who are visiting Australia for less than a year, will be classified as living in another country.
	Average annual growth rate	The average annual growth rate, r, is calculated as a percentage using the formula: where P₀ is the population at the start of the period, P_n is the population at the end of the period and n is the length of the period between P_n and P₀ in years.
	Balance of State or Territory	The aggregation of all Statistical Divisions (SD) within a State or Territory other than its Capital City SD. Further details are included 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.
	Birth interval	Birth interval refers to the interval between two live births. It is usually estimated by subtracting a later birth date from the immediately preceding birth date. The interval between marriage and the first birth is known as the first birth interval, that between the first birth and the second as the second birth interval, that between the second birth and third birth as the third birth interval and so on. A birth interval can be open or closed. An open birth interval is that period following the birth of the last child before the interval is closed by the birth of another child.
	Birth order	Birth order refers to the numerical ordering of the total number of children born alive to a woman, including the present child. The first birth order refers to the first birth, the second birth order to the second birth, the third birth order to the third birth and so on.
	Birth order-specific birth rates	Birth order-specific birth rates are the number of live births of a specific order registered (or occurred) during the calendar year, according to age of mother, per 1,000 of the female estimated resident population of the same age at 30 June. The rates are calculated for each order of birth. The rates at each age (or age group) and birth order are added to provide total fertility rates by birth order, which makes it possible to examine the level of fertility at each birth order and the relative contribution of fertility at each birth order to the total fertility rate.
	Calibration	Calibration refers to the process of correlating a given set of values to a standard. For household estimates, calibration refers to the method of calculating new household weights from either the Census or Labour Force Survey dataset so that the new weights satisfy a set of two or more population marginal constraints and at the same time minimise the difference between the new set of weights and an already existing set of weights.
	Capital city	Capital city refers to the '05' Statistical Division of States and Territories as defined in Statistical Geography: Volume 1 - Australian Standard Geographical Classification (ASGC)(Cat. no. 1216.0).
	Category jumping	Category jumping is the term used to describe changes in travel intentions from short-term to permanent/long-term or vice versa. Category jumping consists of two components - an Australian resident component and an overseas visitor component. The Australian resident component of category jumping for a reference quarter is 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 jump category. Similarly, the number of overseas visitors arriving short-term in a quarter is 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 jump category. Estimates of category jumping are derived by subtracting the Australian resident component from the overseas visitor component.
	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: permanent movements; long-term movements (one year or more); and short-term movements (less than one year). 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 count	The Census of Population and Housing enumerates persons on the basis of where they were located on census night. Characteristics of households are only available according to place of enumeration. The Census also compiles information on people according to their place of usual residence. This information is coded to Statistical Local Areas. 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.
	Children (divorce collection)	Children in the divorce collection are unmarried children of the marriage who were aged under 18 years at the time of application for divorce. Under the Family Law Act 1975 (Cwlth) these may include (in certain cases) adopted and ex-nuptial children and children from a former marriage. Children who are married or aged 18 years or more are not subject to custody and guardianship orders and are excluded.
	Children (marriage collection)	Children in the marriage collection refer to persons under 16 years of age born from previous marriages. The term children should not be confused with the term previous births used in births data (see Previous births).
	Cohabiting couples	Cohabiting couples refer to males and females, both aged at least 15 years, who are in a registered or de facto marriage and are usually resident in the same household
	Completed fertility	The completed fertility rate represents the average number of births a cohort of women have borne. It is obtained by summing the age-specific birth rates experienced by that cohort of women over their reproductive lives.
	Confinement	A pregnancy which results in at least one live birth.
	Country of birth	The classification of countries is the Australian Standard Classification of Countries for Social Statistics (ASCCSS). For more detailed information refer to the Australian Standard Classification of Countries for Social Statistics (ASCCSS) (Cat. no. 1269.0). Recent political developments in Europe and the former USSR have resulted in a number of changes to the ASCCSS. These changes have affected some categories and are detailed in Revisions 1.02 and 1.03 of the ASCCSS.
	Country of residence	Country of residence refers to the country in which travellers regard themselves as living or as last having lived.
	Crude birth rate	The crude birth rate is the number of live births registered during the calendar year per 1,000 estimated resident population at 30 June of that year. For years prior to 1992, the crude birth rate was based on the mean estimated resident population for the calendar year.
	Crude death rate	The crude death rate is the number of deaths registered during the calendar year per 1,000 estimated resident population at 30 June. For years prior to 1992, the crude death rate was based on the mean estimated resident population for the calendar year.
	Crude divorce rate	The crude divorce rate is the number of decrees absolute granted during the calendar year per 1,000 estimated resident population at 30 June. For years prior to 1992, the crude divorce rate was based on the mean estimated resident population for the calendar year. In the interpretation of this rate, it must be kept in mind that a large and varying proportion of the population used in the denominator is unmarried or is below the minimum age of marriage.
	Crude marriage rate	The crude marriage rate is the number of marriages registered during the calendar year per 1,000 estimated resident population at 30 June. For years prior to 1992, the crude marriage rate was based on the mean estimated resident population for the calendar year. In the interpretation of this rate, it must be kept in mind that a large and varying proportion of the population used in the denominator is below the minimum age of marriage or is already married.
	Date of final separation	The date of final separation is the date, given on the application for divorce, from which the period of living apart is calculated for the purpose of establishing grounds for divorce. In determining the date of final separation, a single period of resumed cohabitation of less than three months may be ignored, provided the periods of living apart before and after resumed cohabitation amount to a total of 12 months or more.
	Divorce	Decree absolute of dissolution of marriage.
	Duration of marriage	Duration of marriage is the interval measured in completed years between the date of marriage and the date of divorce.
	Duration of marriage until separation	Duration of marriage until separation is the interval measured in completed years between the date of marriage and the date of separation.
	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)	Estimated resident population (ERP) are estimates of the Australian population obtained by adding to the estimated population at the beginning of each period the components of natural increase (on a usual residence basis) and net overseas migration. For the States and Territories, account is also taken of estimated interstate movements involving a change of usual residence. After each census, estimates for the preceding intercensal period are revised by incorporating an additional adjustment (intercensal discrepancy) to ensure that the total intercensal increase agrees with the difference between the ERPs at the two respective census dates. Estimates of the resident population are based on adjusted (for underenumeration) census counts by place of usual residence, to which are added the number of Australian residents estimated to have been temporarily overseas at the time of the Census. Overseas visitors in Australia are excluded from this calculation. The concept of ERP links people to a place of usual residence within Australia. Usual residence is that place where each person has lived or intends to live for six months or more from the reference date for data collection.
	Fetal death	For fetal deaths a birthweight and period of gestation criterion apply: The delivery of a child weighing at least 500 grams at delivery (or of at least 22 weeks gestation, if birthweight is unavailable) who did not, at any time after delivery, breathe or show any other evidence of life such as heartbeat. The delivery of a child weighing at least 400 grams at delivery (or of at least 20 weeks gestation, if birthweight is unavailable) who did not, at any time after delivery, breathe or show any other evidence of life such as heartbeat. Wherever used, the definition adopted is indicated.
	Fetal death rate	For fetal death rates a birthweight and period of gestation criterion apply: The fetal death rate is the number of fetal deaths per 1,000 live births (who weighed at least 500 grams at birth or of at least 22 weeks gestation, if birthweight was unavailable), plus fetal deaths recorded during the calendar year. The fetal death rate is the number of fetal deaths per 1,000 live births (who weighed at least 400 grams at birth or of at least 20 weeks gestation, if birthweight was unavailable), plus fetal deaths recorded during the calendar year. Wherever used, the definition adopted is indicated.
	First marriage rates	First marriage rates are the number of men or women marrying for the first time during the calendar year, per 1,000 population of never married men or women aged 15 years and over at 30 June.
	Former Yugoslav Republics	Consists of Bosnia-Herzegovina, Croatia, the former Yugoslav Republic of Macedonia, Slovenia, the former Yugoslav Republics of Serbia and Montenegro, and Yugoslavia n.f.d.
	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 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. This definition of a household is consistent with the definition used in the Census. The number of households can be either based on count or estimated resident population.
	Household count	The count of households is the number of households enumerated or counted in the Census. It is not adjusted for underenumeration, 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.
	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.
	Household population	The household population is the estimated resident population (ERP) that usually lives in private dwellings. It is the ERP less the population that usually lives in non-private dwellings.
	Household size	Household size refers to the number of persons in a household.
	Household size propensity	Household size propensity is the probability of a person residing in a household of a particular size.
	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 couple	An Indigenous couple is a couple where either or both partners in the relationship are of Aboriginal or Torres Strait Islander origin.
	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.
	Infant death	An infant death is the death of a live-born child who dies before completing his/her first birthday.
	Infant mortality rate	The number of deaths of children under one year of age in a calendar year per 1,000 live births in the same calendar year.
	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 of a census year population, the first based on the latest census and the second arrived at by updating the previous census date estimate 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 of census year population, the first based on the latest census and the second arrived at by updating the previous census date estimate with intercensal components of population change which do not take account of information available from the latest census.
	Life expectancy	Life expectancy refers to the average number of additional years a person of a given age and sex might expect to live if the age-specific death rates of the given period continued throughout his/her lifetime.
	Long-term arrivals	Long-term arrivals comprise: overseas visitors who intend to stay in Australia for 12 months or more (but not permanently); and Australian residents returning after an absence of 12 months or more overseas.
	Long-term departures	Long-term departures comprise: Australian residents who intend to stay abroad for 12 months or more (but not permanently); and overseas visitors departing who stayed 12 months or more in Australia.
	Main destination	Australian residents travelling overseas are asked on departure for the name of the country in which they intend to spend most time.
	Marital status	Two separate concepts are measured by the Australian Bureau of Statistics. These are registered marital status and social marital status. They have different personal characteristics and are independent variables with separate classifications. Marital status relates to registered marital status which refers to formally registered marriages or divorces for which the partners hold a certificate. Four categories of marital status are identified: never married, married, widowed and divorced.
	Marriage	Under the Australian Marriage Act 1961 (Commonwealth), 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.
	Mean age	The average age of the population.
	Mean population	Mean populations are calculated using the formula: where a is the population at the end of the quarter immediately preceding the 12-month period, and b, c, d and e are the populations at the end of each of the four succeeding quarters. The weights used in the formulation of the mean annual populations have been derived using a mathematical technique which involves the fitting of two quadratic polynomial functions to a series of points.
	Median age at childbearing	The term refers to the age when approximately one-half of the women in a population have their children, either for a birth of particular birth order or for all births. It measures the age at childbearing within the female population, as distinct from the median age of mother at confinement which measures the median age of the women who gave birth in a particular year.
	Median value	For any distribution the median value (age, duration, interval) is that value which divides the relevant population into two equal parts, half falling below the value, and half exceeding it. Where the value for a particular record has not been stated, that record is excluded from the calculation.
	Multiple birth	A multiple birth is a confinement which results in two or more issue, at least one of which is live-born.
	Multistage area sample	Multistage area sample refers to the successive stages adopted for selecting a sample. In the Labour Force Survey, each State or Territory is divided into areas or strata of different types, such as metropolitan, urban, rural or sparsely settled. Each stratum is then divided into Local Government Areas (LGAs). LGAs are selected from each stratum to represent the stratum. Each LGA is also, in turn, divided into Census Collectors Districts (CDs) of around 250 dwellings each. CDs are then chosen to represent an LGA. Each CD is also divided into blocks of about 30 dwellings each. Blocks are selected from each CD to represent the CD. Once a block is selected, all dwellings in the block are listed, but only a few are selected for inclusion in any one survey.
	Natural increase	Excess of births over deaths.
	Neonatal death	For neonatal deaths a birthweight and period of gestation criterion apply: A neonatal death is the death within 28 days of birth of a child weighing at least 500 grams at delivery (or of at least 22 weeks gestation, if birthweight was unavailable) who after delivery, breathes or shows any evidence of life such as a heartbeat. A neonatal death is the death within 28 days of birth of a child weighing at least 400 grams at delivery (or of at least 20 weeks gestation, if birthweight was unavailable) who after delivery, breathes or shows any evidence of life such as a heartbeat. Wherever used, the definition adopted is indicated.
	Neonatal death rate	For neonatal death rates a birthweight and period of gestation criterion apply: The neonatal death rate is the number of neonatal deaths per 1,000 live births (who weighed at least 500 grams at birth or of at least 22 weeks gestation, if birthweight was unavailable). The neonatal death rate is the number of neonatal deaths per 1,000 live births (who weighed at least 400 grams at birth or of at least 20 weeks gestation, if birthweight was unavailable). Wherever used, the definition adopted is indicated.
	Net interstate migration	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 may be either positive or negative.
	Net overseas migration	Net overseas migration is net permanent and long-term overseas migration plus an adjustment for the effect of category jumping.
	Net permanent and long-term overseas movement	The difference between the number of permanent (settler) and long-term overseas arrivals and the number of permanent and long-term overseas 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 reproduction rate	The net reproduction rate represents the average number of daughters that would be born to a group of women if they are subject to the fertility and mortality rates of a given year during their future life. It indicates the extent to which the population would reproduce itself. The net reproduction rate is obtained by multiplying the age-specific birth rates (for female births only) by the proportion of survivors at corresponding ages in a life table and adding the products.
	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 first confinement	A nuptial first confinement is the first confinement in the current marriage and therefore does not necessarily represent the woman's first ever confinement resulting in a live birth.
	Nuptiality	Nuptiality relates to the 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.
	Occupation	Refers to the usual occupation of each person aged between 15 and 64 years as coded according to the ASCO - Australian Standard Classification of Occupations, Second Edition (Cat. no. 1220.0).
	Occupied private dwelling	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).
	Parity progression ratio	Parity progression ratio refers to the proportion of women, with a given number of children, who progress to having another child.
	Part of State	Part of State is used to refer to the remainder of a State outside the Capital City Statistical Division (SD). See also Balance of State or Territory.
	Paternity-acknowledged birth	A paternity-acknowledged birth refers to an ex-nuptial birth where paternity was acknowledged.
	Perinatal death	A perinatal death is a fetal or a neonatal death.
	Perinatal death rate	For perinatal death rates a birthweight and period of gestation criterion apply: The perinatal death rate is the number of perinatal deaths per 1,000 live births (who weighed at least 500 grams at birth or of at least 22 weeks gestation, if birthweight was unavailable), plus fetal deaths recorded during the calendar year. The perinatal death rate is the number of perinatal deaths per 1,000 live births (who weighed at least 400 grams at birth or of at least 20 weeks gestation, if birthweight was unavailable), plus fetal deaths recorded during the calendar year. Wherever used, the definition adopted is indicated.
	Permanent arrivals	Permanent arrivals (settlers) comprise: travellers who hold migrant visas (regardless of stated intended period of stay); New Zealand citizens who indicate an intention to settle; and those who are otherwise eligible to settle (e.g. overseas-born children of Australian citizens). This definition of settlers is used by the Department of Immigration and Multicultural Affairs (DIMA). Prior to 1985 the definition of settlers used by the Australian Bureau of Statistics 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 the DIMA.
	Permanent departures	Permanent departures comprise movements of persons who on departure state that they do not intend to return to Australia.
	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.
	Population turnover	Population turnover is the sum of interstate arrivals and departures during a year expressed as a proportion of the resident population of the State or Territory at the beginning, or mid-year, or at the end of the year. Population turnover, however, can also incorporate permanent and long-term arrivals and departures (adjusted for category jumping) to and from each State or Territory during a year.
	Previous births	Previous births refer to children born alive (who may or may not be living) to a mother prior to the registration of the current birth in the processing period. In some States, legitimised and legally adopted children may also be included. Due to variation in data collection and processing methods across States and Territories, different definitions of the concept of previous births have been applied. All previous births of the mother includes all births prior to the current confinement, regardless of nuptiality and paternity. Previous births of the current relationship where paternity was acknowledged includes all births prior to the current confinement where the current confinement relates to a nuptial birth, or an ex-nuptial birth where paternity was acknowledged.
	Previous issue	See Previous births.
	Private dwelling	A private dwelling (PD) 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.
	Propensity	See Household size propensity.
	Purpose of journey	On arrival in, or departure from, Australia all overseas visitors and Australian residents are asked to state their main purpose of journey. From September 1994, all statistics relating to purpose of journey have been published using the following categories: convention/conference business visiting friends/relatives holiday employment education other In tabulations of data collected before September 1994, the 'Other' category includes 'In transit'. The 'Holiday' category includes both 'Student vacation' and 'Accompanying business visitor'.
	Rate of population growth	Population change over a period as a proportion (percentage) of the population at the beginning of the period.
	Remarriage rates	Remarriage rates are the number of remarrying men or women per 1,000 population of widowed and divorced men or women of the same age at 30 June. The rates are separately calculated for widowed or divorced men or women by appropriately adjusting the numerator and denominator of the rates.
	Replacement fertility	Replacement level fertility is the number of babies a woman would need to have over her reproductive life span to replace herself and her partner. Given the current mortality of women up to age 49, replacement fertility is estimated at 2.1 babies per woman.
	Residents temporarily overseas	Residents temporarily overseas are Australian residents who are overseas for a period less than 12 months.
	Return migration	Return migration is the emigration of former settlers to their country of birth.
	Rotation group	The sample of households for the monthly Labour Force Survey is divided into eight groups of approximate equal size, called rotation groups. They are called rotation groups because each group stays in the sample for eight consecutive months and is then rotated out of the sample and is replaced by another group that is rotated into the sample for another period of eight months.
	Sample list of non-private dwellings	For the purposes of the Labour Force Survey (LFS), a sample list of non-private dwellings (NPDs) refers to the sample of NPDs selected from a list of all NPDs in Australia. It includes: hostels for the homeless, night shelters and refuges; hotels and motels; hospitals and homes; religious and educational institutions; prisons; boarding houses and others; Aboriginal settlements; and short-term caravan parks and camping grounds. It is from the sample list of NPDs that persons resident in NPDs are selected for the LFS. Each NPD is given a chance of selection proportional to the number of people accommodated within it.
	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 appropriately selecting the numerator and denominator of the ratio.
	Short-term arrivals	Short-term arrivals comprise: overseas visitors who intend to stay in Australia for less than 12 months; and Australian residents returning after a stay of less than 12 months overseas.
	Short-term departures	Short-term departures comprise: Australian residents who intend to stay abroad for less than 12 months; and overseas visitors departing after a stay of less than 12 months in Australia.
	Standardised death rates	Standardised death rates enable the comparison of death rates between populations with different age structures by relating them to a standard population. The ABS standard populations relate to the years ending in 1 (eg 1991). The current standard population is all persons in the 1991 Australian population. They are expressed per 1,000 or 100,000 persons. There are two methods of calculating standardised death rates: The direct method - this is used when the populations under study are large and the age-specific death rates are reliable. It is the overall death rate that would have prevailed in the standard population if it had experienced at each age the death rates of the population under study. The indirect method - this is used when the populations under study are small and the age-specific death rates are unreliable or not known. It is an adjustment to the crude death rate of the standard population to account for the variation between the actual number of deaths in the population under study and the number of deaths which would have occurred if the population under study had experienced the age-specific death rates of the standard population. Wherever used, the definition adopted is indicated.
	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 stay	Overseas visitors are asked on arrival for the name of the State or Territory in which they intend to spend the most time.
	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: the population (estimated resident population); the mother (birth collection); or the deceased (death collection). 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 Local Areas	Statistical Local Areas (SLAs) consist of one or more Census Collection Districts at a census date. They can be based on legal Local Government Areas or parts thereof, or any unincorporated area. They cover, in aggregate, the whole of Australia without gaps or overlaps. SLAs are used in defining and compiling data at the part of State level. (Further details are included in Australian Standard Geographical Classification (ASGC) (Cat. no. 1216.0).)
	Total fertility rate	The sum of age-specific fertility rates (live births at each age of mother per female population of that age). It represents the number of children a woman would bear during her lifetime if she experienced current age-specific fertility rates at each age of her reproductive life.
	Total first marriage rate	The total first marriage rate is obtained by summing age-specific first marriage rates (calculated by using total population) and indicates the number of males or females who will ever marry per 1,000 males or females in the population. The population aged under 15 years is excluded from this calculation.
	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.
	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.