Provisional migration estimates by age-sex now available – Media release
19 December 2018
Provisional international migration estimates are now available by age group and sex, Stats NZ said today.
“This is the first time our customers are able to see the new provisional migration estimates by key demographics such
as age and sex," population insights senior manager Brooke Theyers said.
"Migration is usually concentrated in certain age groups and is sometimes different between males and females. So, these
breakdowns of migration are important for customers to understand migrant flows into and out of New Zealand.”
“Accurate measures of migration by age group flow through into many other data uses, including official population
The downloadable files below and the graphs in this release give age-sex estimates for migrant arrivals, migrant
departures, and net migration (arrivals minus departures).
They are an indication of the migration statistics that will be available when our new outcomes-based approach is fully
adopted in January 2019.
Half of migrants aged 20–34 years
The migration estimates in the downloadable file ‘Estimated annual migrant arrivals, migrant departures, and net
migration, by age group and sex, 2014–18 – CSV’ and figure 1 show that both arrivals into New Zealand, and departures
from New Zealand, are concentrated in the 20–34 age range. In the year ended October 2018, 46 percent of migrant
arrivals and 49 percent of migrant departures were aged 20–34 years.
“It’s also notable that the uncertainty in these provisional annual estimates is relatively small,” Mrs Theyers said.
“While the relative uncertainty is higher for recent monthly data, on an annual basis the uncertainty shrinks.”
Migrant flows more accurately measured by outcomes data
We have been developing an outcomes-based approach to estimate migration into and out of New Zealand. Final estimates
will be available 17 months after the reference month, but provisional estimates will be available after one month to
maintain the timeliness of migration statistics (see Update on the development of provisional external migration statistics
The outcomes-based approach is a way of classifying border crossings as short-term or long-term, based on whether
travellers actually spend 12 months (or more) of the following 16 months in New Zealand. By comparison, the
intentions-based approach, which we used previously, relied on the stated plans of people when they arrived in or left
The new methodology is completely independent of passenger cards. It provides a sustainable ongoing method of
classifying travellers now that passengers are no longer required to complete departure cards as they leave New Zealand.
Previously released migration estimates show that arrivals and departures are typically higher in the outcomes-based
measure than the traditional intentions-based measure (see Outcomes versus intentions: Measuring migration based on travel histories
and Provisional migration estimates by citizenship now available
). However, net migration (arrivals minus departures) using outcomes has been lower and higher than intentions at
different times. In recent years, net migration using outcomes has been lower than intentions.
Net migration gains across all age groups
The latest annual data, for the year ended October 2018, indicates all age groups gained people from international
migration. Nearly half the gains were at ages 25–39 years (see figure 2).
“Although the largest arrival and departure flows were at ages 20–34 years, the net difference between arrivals and
departures was largest at ages 25–39 years,” Mrs Theyers said.
Females aged 25–29 years had a net migration gain during the year of about 5,300. This was the largest net gain of any
five-year age group. However, over all ages, the net migration gain of males and females was roughly equal.
New release schedule
A new release, called International travel, will replace statistics on short-term movements that were previously published in two different releases – International travel and migration (ITM) and International visitor arrivals to New Zealand (IVA).
Long-term movements will be published in the new International migration release. Both new releases will be published on
the same day, up to 30 working days after each reference month. November data, previously published just before
Christmas, will now be published in January, and December data in February (see Release calendar
The new release schedule largely reflects the need to use integrated administrative data (ie Stats NZ’s Integrated Data Infrastructure
) to provide place-of-residence within New Zealand of migrants and short-term resident travellers. This replaces
information from the departure card. The timing is also affected by the new method to produce provisional migration
For more information about the changes to migration statistics see Migration Data Transformation Project
, which includes mock-ups of how the Excel summary tables will look in the new International travel and International
migration releases from January 2019. Feedback on these new tables is welcome: email email@example.com
Text alternative for figure 1
An age-sex pyramid or bar graph with discrete data points showing migrant arrival and migrant departure numbers by
five-year age group, for males and females separately, for the year ended October 2018. Data for the year ended October
2018 is provisional. Each provisional data point has 95 percent uncertainty bounds to show the level of confidence in
the estimate. Data is available in the downloadable file ‘Estimated annual migrant arrivals, migrant departures, and net
migration, by age group and sex, 2014–18 – CSV’.
Text alternative for figure 2
An age-sex pyramid or bar graph with discrete data points showing net migration numbers by five-year age group, for
males and females separately, for the year ended October 2018. Data for the year ended October 2018 is provisional. Each
provisional data point has 95 percent uncertainty bounds to show the level of confidence in the estimate. Data is
available in the downloadable file ‘Estimated annual migrant arrivals, migrant departures, and net migration, by age
group and sex, 2014–18 – CSV’.
For more information about these statistics: