Working out how many electorates there should be

Before the Representation Commission can review electorate boundaries, the Government Statistician at Stats NZ works out how many Māori and general electorates there should be and the average population of each electorate.

The Electoral Act 1993 fixes the number of general electorates in the South Island at 16. The number of Māori electorates and North Island general electorates can change depending on how many people live in them compared with how many people live in South Island general electorates.

The Government Statistician finds the average population of Māori and general electorates by dividing the total population of those electorates by the number of those electorates.

Working out how many people are in each electorate type

The Government Statistician uses the census and the results of the Māori Electoral Option to work out the population of:

  • Māori electorates
  • general electorates in the North Island
  • general electorates in the South Island.

The law sets out the formula the Government Statistician uses to work out the population of Māori electorates. The formula includes:

  • the number of people registered on the Māori rolls
  • a proportion of people of Māori descent who haven’t enrolled to vote
  • a proportion of people of Māori descent who are younger than 18 years old.

The population of general electorates is the ordinarily resident population at the last census minus the population of Māori electorates.

The Government Statistician uses these populations to help work out the number of electorates and the average populations of those electorates.

Working out the average number of people in a South Island general electorate

The Government Statistician works out the average population of a South Island general electorate by dividing the population in those electorates by 16.

For example, 954,871 people lived in South Island general electorates in 2013. The Government Statistician divided that by 16 to get an average of 59,679 people in each electorate.

The Government Statistician uses this average to work out the number of Māori electorates and North Island general electorates. The Representation Commission also uses this average as a population quota when it works out boundaries of South Island general electorates.

Working out the number of Māori electorates and North Island general electorates

The Government Statistician works out the number of Māori electorates and North Island general electorates by dividing the total populations of those electorates by the average population of a South Island general electorate.

For example, 420,990 people were in Māori electorates in 2013. The Government Statistician divided that by 59,679 to get 7 Māori electorates.

The Government Statistician rounds the number of Māori electorates and North Island general electorates to the nearest whole number.

Working out the average number of people in Māori electorates and North Island general electorates

The Government Statistician finds the average population of Māori and North Island general electorates by dividing the total population of those electorates by the number of those electorates.

For example, 2,867,110 people were in North Island general electorates in 2013. The Government Statistician divided that by 48 North Island general electorates to get an average of 59,731 people in each electorate.

The Representation Commission uses these averages as population quotas when it works out boundaries for Māori electorates and North Island general electorates.

What happens next?

The Government Statistician writes a report on the electoral populations and number of electorates for the Representation Commission to use in the boundary review.

What happens in a boundary review?