One in seven New Zealanders did not fully complete the 2018 Census, according to information from Statistics New
Statistics New Zealand chief executive Liz MacPherson provided information
to Government yesterday indicating 700,000 Kiwis either didn't partake in the survey at all, or did not fully complete
The release of the 2018 data has already been delayed
The SMC asked experts to comment on their use of census data and the impact of these issues. Please feel free to use
these comments in your reporting.
John McDermott, Executive Director, Motu Economic & Public Policy Research, comments:
"Of the 15 research staff at Motu, six will use Census or Census-related data nearly every day. The Census is an
extremely valuable resource for research because it collects information on small populations, on small areas and from
the same people across multiple domains. People in Aotearoa are very mobile and the frequency of Census collection,
therefore, needs to be higher than in more stable countries so that we know what is changing and where.
"This research feeds into policy decisions that make a difference to the future wellbeing of New Zealanders. Without
official Census data, anecdote and intuition would reign without evidence to support or debunk partisan vagaries. Just
in the last year, our researchers have used Census data to examine income inequality, migrants’ settlement experience,
the gender pay gap, the housing market, the cost of poor [quality] housing, household greenhouse gas emissions, and firm
"Nobody can deny that the 2018 Census was problematic. Secure data labs around Aotearoa have echoed with the sound of
raging introverts stressing over how to achieve their research targets with the delay and less relevant data that won’t
be taken as seriously, because in 2019 what politician cares what was happening six years ago?
"Even if StatsNZ makes sensible technical adjustments to turn the available 2018 Census data into representative
national statistics, the microdata (which is the main form of the Census data that we use) will be of lower quality,
making the census a less valuable research resource. However, nothing can fill the gap that would be left if Census data
were not collected.
"After the 2011 Christchurch Earthquake, the Census was deferred by two years. What’s done is done but the best way
forward to mitigate problems that have been generated is to return the Census to the old timeline and run it in 2021
(though this would require a law change). That’s enough time for the lessons from 2018 to be taken on board, StatsNZ to
be resourced to ensure a successful census distribution and collection, and for researchers to gain a handle on the data
before it all changes again."
No conflict of interest.
Peter Crampton, Professor of Public Health, Kōhatu - Centre for Hauora Māori, University of Otago, comments:
"The Census is an essential tool for good policymaking that has a focus on equity, and for monitoring social and
"Government, policymakers, iwi, community group and interested citizens are dependent upon high quality, authoritative
data on which to base their analyses, plans, proposals and funding formulas. For example, in the health sector, the
major funding formula for all DHBs is entirely dependent upon accurate population counts and other demographic data.
Administrative data, the Integrated Data Infrastructure (IDI), and other data sources can often provide high-quality
data that are useful for many purposes, but they do not provide systematic and complete demographic and household
information for the total population, which must come from the Census.
"It is possible to predict which population groups are most likely to be undercounted in the Census. Typically these
groups include a preponderance of marginalised, disenfranchised, high-needs people, whānau and communities — those for
whom good social policy is of the highest priority. If these groups become invisible in the Census then policymaking
becomes doubly difficult and some of the least advantaged communities are at risk of becoming further marginalised.
"My experience of Statistics New Zealand over a number of censuses is that the staff who lead the census process are
expert, dedicated and completely committed to achieving a successful outcome."
Conflict of interest statement: I have used census data for research purposes for about thirty years. There was no
external funding source for preparing these comments. The views, opinions, findings and conclusions or recommendations
expressed in these comments are strictly those of the author. They do not necessarily reflect the views of the
institution where the author currently works. The comments are presented not as policy, but with a view to inform and
stimulate wider debate. Peter Crampton is a member of the Government’s Health and Disability System Review panel; the
views expressed here are his own and not those of the panel.