3222.7 - Population Projections, Northern Territory, 1999 to 2021

ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 25/07/2001

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Explanatory Notes Explanatory Notes Glossary Data Cube (I-Note) Technical Note Data Source	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 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 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 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. At 30 June The date in the year to which the data refers to. 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. Birth The delivery of a child, irrespective of the duration of pregnancy, who, after being born, breathes or shows any other evidence of life such as a heartbeat. Category jumping Category jumping is the term used to describe changes between intended and actual duration of stay of travellers to and from Australia, such that their classification as short-term or as long-term/permanent movers is different at arrival from that at departure. 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. Estimated resident population The concept of estimated resident population (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 in a reference year. The ERP is an estimate 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 the estimated interstate movements involving a change of usual residence. Estimates of the resident population are based on census counts by place of usual residence, to which are added the estimated net census undercount and Australian residents estimated to have been temporarily overseas at the time of the census. Overseas visitors in Australia are excluded from this calculation. 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. 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. 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 or 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. Median age The median age is the age 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. Natural increase The excess of births over deaths. Net internal migration The difference between the number of persons who have changed their place of usual residence by moving into a defined geographical area 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. 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 during a specified time period. 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. Permanent arrivals (settlers) 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 (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 the DIMA. Permanent departures Permanent departures are Australian residents (including former settlers) who on departure state that they are departing permanently. 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 each census, intercensal population growth also includes an allowance for intercensal discrepancy. Rate of population growth Population change over a period as a proportion (percentage) of the population at the beginning of the period. 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. SLA Code Name and numerical code of a Statistical Local Area classified by State/Territory, Statistical Division and Statistical Subdivision from the Australian Standard Geographical Classification (ASGC 2001). 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. Document Selection These documents will be presented in a new window.