A Māori data group is concerned that up to ten percent of the population may be missing in the 2018 census. For Māori, the extent of the problem could be worse.
Early figures for the 2018 Census show only 90 percent of individuals responded. That's almost a 5% decrease compared to the 2013 Census preliminary results.
Donna Cormack, a senior researcher at the University of Auckland and Otago says, "Māori are usually under-enumerated compared to the total population so if there has been an impact on response rates, then it's likely to have a disproportionate impact on Māori."
Te Mana Raraunga are concerned that the 2018 census may yet be the poorest quality enumeration of Māori in recent history. They are questioning methods used by Stats NZ to fill in missing Māori data that includes extensive imputation.
Cormack says, "There's different methods they can use to do that but because the impacts going to be potentially large for Māori, Māori really need to be involved in any decisions around those methodologies."
Government Statistician Liz MacPherson says, “While the hypotheses that the Māori response rate for this census may be lower than for the general population is a reasonable one, Stats NZ is still working through the census reconciliation process. We simply do not know yet how effective our extensive targeted efforts to encourage Māori to complete the census have been.”
MacPherson says Stats NZ was acutely aware of the need to connect with Māori throughout the country, especially in areas where there has been low census coverage in the past, including Northland and the East Coast. Stats NZ are now commissioning two independent reviews of the 2018 Census.
“Stats NZ understands how important the census is for all NZers, including for Māori and for other groups.”
“We worked hard and put a lot of effort into the census. We are keen to learn from what worked and what didn’t, so we can ensure that future censuses are as successful as possible."
The census count of the Māori population is used to determine the boundaries and number of Māori electorates which also depends on the number of Māori who choose to be registered on the Māori electoral roll.
Cormack fears that large numbers missing from the census could mean a reduced number of Māori electorates and the loss of Māori seats which are not entrenched.
Final figures for the 2018 Census will be released early next year.