New Zealand Subnational Abridged Period Life Tables 2017–2019

Method used for the 2017–2019 subnational abridged period life tables: The 2017-2019 subnational abridged period life tables are published along with the national complete period life tables, using statistical model introduced from 2017–2019 life tables. The statistical model was developed to estimate the death rate for age intervals (0, 1–4, 5–9,...,90+) by sex for subnational populations. The release includes subnational life tables for the 2017-2019 period, with a measure of uncertainty (credible intervals) for each of the life table functions, with the median as well as 95 percent limits. The true value of the death rate will be within the 2.5th and 97.5th percentiles, 95 percent of the time, given the input data and the assumed statistical model. For example we can say that 95 percent of the time life expectancy at birth for a male in Northland will be between 78.2 and 79 years, based on the 2017-2019 period life tables. Additional subnational life tables included for 2017–2019 National and subnational period life tables: 2017–2019 continues to extend on subnational life tables released. We can do this because the new statistical model enables us to show uncertainty measures, which display the greater uncertainty associated in estimating smaller populations, particularly in small geographic areas. New life tables included in the 2017–2019 release include: Pacific, Asian, and Eurother life tables by regional council life tables by district health board Māori, non-Māori, Pacific, Asian, and Eurother life tables by district health board life tables based on the 2018 New Zealand deprivation index (NZDep2018) decile district health board life tables based on NZDep2018 (quantile). Data sources The data used to construct the 2017–2019 subnational life tables comprises: Deaths registered in New Zealand in the December years 2017–2019, respectively, by date of death, date of birth, sex, ethnicity, and geographic area of usual residence. The estimated resident population of New Zealand at 30 June 2018, by age, sex, ethnic group, and geographic area of usual residence. Regional council of usual residence was a variable input to the imputation model for missing ethnicity response (see Ethnicity non-response in deaths data). Death registrations We use death registrations as the numerator to derive the death rates. In 2017–2019, 100,920 deaths were registered in New Zealand, made up of 51,471 male and 49,449 female deaths. The level of non-response to the ethnicity question in death registrations has been declining over time. There was no response to the ethnicity question for 231 deaths in 2017–2019 (0.2 percent of all deaths). Death records with missing ethnicity response are imputed using a statistical approach based on records with observed ethnicity response. Read Ethnicity non-response in deaths data below for more information. Population estimates The 2017–2019 subnational life table calculations use, as the population denominator, the estimated resident population at 30 June 2018 – the mid-point of the period. Methodology See New Zealand period life tables: Methodology for 2017–2019 for more detailed methods used to construct the life tables. Comparability of ethnic life tables All ethnic mortality measures should be interpreted with caution because of changes in ethnic concepts and data sources. This includes changes over time as well as differences in measurements between data sources: We applied the statistical model used for the derivation of death rates at the detailed demographic level in 2017–2019. All life table components are derived based on the estimated death rates including uncertainty measures. Due to changes to the census ethnicity question, population estimates for ethnic groups are not necessarily comparable. Death registrations and population data are broadly comparable for ethnic groups. However, the death registration form has been redesigned in the past (eg in 1995). Read New Zealand Period Life Tables – Significant events impacting this study series for more detailed information on historic changes to the two data collections and other changes. Deprivation index (NZDep2018) The life tables by deprivation area use the New Zealand 2018 index of socio-economic deprivation. It combines census data relating to income, home ownership, employment, qualifications, family structure, housing, and access to transport and communication, to produce a score for each meshblock in New Zealand. These scores are grouped into 10 categories (deciles), where 1 represents the areas with the least deprived scores and 10 the areas with the most deprived scores. A value of 10 therefore indicates that a meshblock is in the most deprived 10 percent of areas in New Zealand. More information We produce national abridged period life tables on an annual basis. These are not as detailed as complete life tables, as abridged life tables present functions for grouped ages rather than single years of age, and are not derived by ethnicity. Abridged period life tables are updated annually and will be available in February each year. See New Zealand Subnational Abridged Period Life Tables in DataInfo+ for more information about life tables, including information about methods. en-NZ