Travel - NZ-resident traveller departures by main destination, purpose, age and sex (Monthly) Jan 2006–Dec 2017

The loss of information from the removal of the departure card means Stats NZ will no longer provide resident departure series.
From November 2018, resident arrivals is the only source of information for short-term travel of NZ residents.

Country of main destination: the country where a New Zealand-resident traveller will spend the most time while overseas. Departure cards do not ask travellers which other countries they intend to visit on the same trip.
Travel purpose: the main purpose for the trip overseas. Categories are holiday, visiting friends and relatives, business, conferences and conventions, education, and other.

http://datainfoplus.stats.govt.nz/Item/nz.govt.stats/f705ca38-ea6e-453f-b1d9-a95dc0fcaf59#

A person may change their intentions after their arrival or departure, which may mean the recorded passenger type becomes incorrect. Stats NZ does not revise published statistics for such changes, but advises that the published figures remain a good indicator of trends in permanent and long-term migration.
Data is derived from a sample of records and hence may contain sample error. Caution should be used when using data with low cell values.

The statistics in this release relate to the number of passenger movements from New Zealand, rather than to the number of people – that is, the multiple movements of individual people during a given reference period are each counted separately. For example, a New Zealand resident making five business trips overseas within a year would be counted as five departures.

From August 2016, international travel and migration data started being processed using a new, upgraded processing system. The new system uses improved methodology, which takes greater account of travellers' history in addition to intentions stated on the arrival and departure cards. It also makes greater use of automation in the processing and classification of passenger types. There were no revisions to the historical data with this system and methodology changes.

At URL provided, select 'Tourism > International Travel and Migration - ITM > NZ-resident traveller departures by main destination, purpose, age and sex (Monthly). All variables from 2005 were selected to create this dataset.

International travel and migration statistics count passengers arriving into and departing from New Zealand. Passengers are split into one of three passenger types: overseas visitors, New Zealand-resident travellers, and permanent and long-term migrants.
Arrivals and departures of overseas visitors and New Zealand-resident travellers are key indicators of tourism and travel. Permanent and long-term migration is a component of New Zealand’s population change, along with births and deaths. Migration affects the composition of the population as well as population size.
International travel and migration statistics are based on electronic arrival and departure records for each international passenger, supplied to Stats NZ by the New Zealand Customs Service. These electronic records include flight and passport details, such as date of travel, date of birth, sex, and country of citizenship.