Estimated and projected median age in New Zealand

Ethnicity: the ethnic group or groups that people identify with or feel they belong to. Ethnicity is a measure of cultural affiliation, as opposed to race, ancestry, nationality, or citizenship. Ethnicity is self-perceived and people can belong to more than one ethnic group.
Median projection: Assuming medium fertility, medium mortality, and medium net migration.
Natural increase: live births minus deaths
Net migration: Long-term arrivals to the area minus long-term departures from the area. This includes migration within New Zealand

It is important to note that these ethnic populations are not mutually exclusive because people can and do identify with more than one ethnicity. People who identify with more than one ethnicity have been included in each ethnic population.
Note: Net migration in the year ending June 2023 was much higher than the median net migration assumption used in the updated projections.

http://datainfoplus.stats.govt.nz/Item/nz.govt.stats/639b804e-9bd7-4b49-99c1-019d5e59928f#

The projections are not predictions. The projections are designed to meet both short-term and long-term planning needs, but are not designed to be exact forecasts or to project specific annual variation. These projections are based on assumptions made about future fertility, mortality, migration, and inter-ethnic mobility patterns of the population. Although the assumptions are carefully formulated to represent future trends, they are subject to uncertainty. Therefore, the projections and associated probability intervals should be used as guidelines and an indication of the overall trend, rather than as exact forecasts.

At URL provided, select 50% median scenario. All remaining variables are selected.

National population estimates give the best measure between census dates of the population that usually lives in an area, by ethnic group, for the total New Zealand area.

This dataset contains 2018-base (update) projections of the European or Other (including New Zealander), Maori, Asian, Pacific, Middle Eastern/Latin American/African, Chinese, Indian, and Samoan ethnic populations usually living in New Zealand (released September 2022). These projections have the estimated resident population of each ethnic group at 30 June 2018 as a base.