Nature of data
The statistics in this release are based on final international travel and migration counts. They relate to the number of passenger movements, rather than to the number of people – that is, the multiple movements of individual people during a given reference period are each counted separately.
Changes in passenger type
In the preparation of international travel and migration statistics, the passenger type (overseas visitor, New Zealand-resident traveller, or permanent and long-term (PLT) migrant) is primarily determined by the passenger's response, on the arrival or departure card, to the questions on where they live and their length of stay or absence. If the person's intention changes later during the trip, this passenger type may no longer be correct. For example, a person may come to New Zealand with the declared intention of settling permanently (PLT migrant), but in fact may return overseas after a few months (overseas visitor). Data users should recognise the limitations inherent in the information supplied by travellers.
Sampling accuracy
The statistics for short-term passenger movements by country (that is, overseas visitor arrivals by country of last permanent residence and New Zealand-resident departures by country of main destination) are derived from a systematic random sample taken each month from arrival and departure cards, and are therefore subject to sampling errors. However, total counts for arrivals and departures of overseas visitors and New Zealand residents are actual counts, which are not subject to sampling errors. Figures for PLT arrivals and departures are also actual counts and have no sampling errors.
Infoshare and INFOS databases
All data in the Hot Off The Press tables are available through the Infoshare database (www.stats.govt.nz/infoshare), a free-of-charge online tool that gives you access to a range of time-series data. International travel and migration data are currently available through two subjects within Infoshare:
- International travel and migration (under Tourism on the Browse page)
- External migration (under Population on the Browse page).
The international travel and migration subject is under development, with more detailed cross-tabulations being progressively added. This will eventually replace the external migration subject, but both will remain available until development of the international travel and migration subject is complete.
Both subjects are also available in the INFOS database (for subscribers only). Where feasible, INFOS series identifiers are shown in the Hot Off The Press tables.
New Zealand-resident short-term departures
The commentaries relating to New Zealand-resident short-term departures are based on data for the country of main destination – that is, the country where each departing person intended to spend most of their time while away from New Zealand.
Seasonally adjusted and trend series
The purpose of seasonally adjusting a time series is to measure and remove the varying seasonal components in the series (for example, there are more visitor arrivals during the New Zealand summer, due to the warmer weather and longer daylight hours). This makes the data for adjacent months more comparable.
An improved seasonal adjustment process was adopted in March 2009. The new process continues to use Statistics NZ's standard seasonal adjustment package, X-12-ARIMA, but incorporates enhancements which allow the specification and adjustment of additional calendar effects. These include the number and type of trading days in the month (as more people generally arrive and depart on Friday, Saturday and Sunday), and holiday periods which have important effects on travel but in different months each year (eg Easter can be in March or April). The additional adjustments for the monthly seasonally adjusted series are:
- permanent and long-term arrivals: no additional adjustments
- permanent and long-term departures: no additional adjustments
- visitor arrivals: Chinese New Year, Easter, April/May school holidays, June/July school holidays, daily trading day
- visitor departures: Chinese New Year, Easter, September/October school holidays
- New Zealand-resident traveller arrivals: Easter, April/May school holidays, September/October school holidays, weekday/weekend trading day
- New Zealand-resident traveller departures: Chinese New Year, Easter, April/May school holidays, June/July school holidays, September/October school holidays, weekday/weekend trading day
- all composite series (total arrivals, total departures, total passenger movements, net permanent and long-term migration) are a combination of the series above.
Quarterly seasonally adjusted series were introduced in April 2009. The quarterly series are adjusted independently of the adjustments made to the monthly series. Hence, quarterly figures may not equal the sum of monthly seasonally adjusted figures. The additional adjustments made to the quarterly series are:
- permanent and long-term arrivals: no additional adjustments
- permanent and long-term departures: no additional adjustments
- visitor arrivals: Easter, June/July school holidays
- visitor departures: Easter, September/October school holidays
- New Zealand-resident traveller arrivals: September/October school holidays
- New Zealand-resident traveller departures: Easter, April/May school holidays, June/July school holidays
- all composite series (total arrivals, total departures, total passenger movements, net permanent and long-term migration) are a combination of the series above.
Seasonally adjusted and trend data back to January 1996 are subject to revision each month. The size of these revisions is expected to be minimal, with the largest revisions occurring in the months immediately prior to the current month. Data before January 1996 is not revised. This cut-off is used because of the change to a four-term school year in 1996, which resulted in changes to the seasonal patterns of the New Zealand-resident arrivals and departures series.
Permit type
With the exception of New Zealand citizens, Australian citizens and a small number of other people exempt under the Immigration Act 1987, everyone entering New Zealand is required to obtain a permit to remain in New Zealand. People already in New Zealand can apply for a permit renewal or a new permit of a different type. However, Statistics NZ only holds data on the permit type that an individual was given on arrival.
The determination of passenger type (as an overseas visitor, New Zealand-resident traveller or PLT migrant) by Statistics NZ is independent of the permit type a person holds. Passenger type is based on the time spent in and out of New Zealand, determined from past arrivals and departures of a person and responses to questions on the arrival or departure card.
Permit type data is available from July 2003 for arrivals of short-term overseas visitors and PLT migrants. It is not available for arrivals of short-term New Zealand-resident travellers or for departures of any passenger type.
Processing system
The current international travel and migration processing system, which incorporates scanning and image recognition technology, was first used to process the June 2004 arrival and departure cards. The determination of passenger type (overseas visitor, New Zealand-resident traveller or PLT migrant) and capture of the information required for the sample are done automatically for the majority of the cards. Operator intervention is only required for approximately one-tenth of the cards. The system is used only for the production of statistics.
Users should be aware of the changes to the processing system when comparing data for June 2004 onwards with data for earlier periods
More information
For more information, follow the link from the technical notes of this release on the Statistics NZ website.
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Timing
Timed statistical releases are delivered using postal and electronic services provided by third parties. Delivery of these releases may be delayed by circumstances outside the control of Statistics NZ. Statistics NZ accepts no responsibility for any such delays.