Is this the end of the Census as we know it? Stats NZ wants your ideas

Stats NZ is looking for some feedback from Kiwis.

Two weeks ago the first results of the 2023 Census were released. But even as the final forms were being collected last July, Government Statistician Mark Sowden indicated it might have been the last Census as we know it. Sure enough, Stats NZ is now running a public consultation on the future of the Census in New Zealand. It wants to know how you think Kiwis should be counted in future. Submissions are open until 5pm on June 18, 2024.

Census 1851–2023

Times have changed since New Zealand carried out its first Census in 1851 and recent Censuses have faced headwinds.

Only Europeans were counted in 1851, but the questions did include some topics that remain relevant today; such as disability, education and productivity.

In early Censuses, the head of a household was responsible for completing a single household form on Census night. The current format, using dwelling and individual forms, was introduced more than a century ago in 1921.

Population counts for Māori began in 1857 but not until 1951 - one hundred years after the first Census - did the entire population complete the same Census.

More recently, the failed transition to an online Census in 2018 led to the resignation of the Chief Statistician. Stats NZ used additional data sources, known as admin data, in an effort to plug the gaps.

Last year’s Census response rate was 88.8 per cent, slightly below Stats NZ’s target of 90 per cent, and well below the 2013 response rate of 92.9 per cent.

As planned for the 2023 Census, responses were combined with admin data to produce information on 99.1 per cent of the population. Stats NZ estimates only 44,000 individuals were not counted by either Census or admin data.

Looking to Census 2028

Stats NZ might not require everyone to complete a Census form in 2028.

Sowden said the 2023 Census cost about $316 million, including $133m spent on collection operations. Before committing to the same Census in 2028, “we have the opportunity to think differently, to try and provide better data for New Zealanders, to try and reduce the cost to New Zealanders, both in terms of their time, but also the cost to the taxpayer as well.”

Census 2028 could use what Sowden described as a three-legged approach of admin data, surveys, and targeted collections.

Government Statistician Mark Sowden says Census 2028 could use a mixed approach in collecting data.

Sowden said the only firm decision made so far is that Stats NZ will make more use of admin data than in the past. “At the very least we’re looking at flipping what we did in Census 2023 - where we had forms supplemented by admin data - flipping that on its head and saying we’ll use admin data first and then forms to supplement the gaps.”

The range of options for surveys includes changing the number of people surveyed, changing the size of the form, or surveying more frequently.

Why doesn’t the Government use the data it already has?

The Government knows a lot about us, so why doesn’t Stats NZ use that data?

A common complaint is, “Why are you asking me this information? I have already paid my taxes, you must have this information about me already.” The Inland Revenue Department (IRD) certainly has the information, but Stats NZ may not.

Essentially, an admin data-first approach is: Start with IRD data on income, identify the gaps and work out how to fill them.

But exactly how to do this isn’t always clear. Former Government Statistician Len Cook draws on archaeology for an analogy. “The Census provides a skeleton, admin data is a bit like fossils - fitting fossils to a skeleton is very hard.”

Former Government Statistician Len Cook

Sowden emphasised that Stats NZ has a team whose job is “to understand how admin data is collected, how it might be used, and how much of the population it covers. One of the things we need to do is be far more open about that so that New Zealanders can see our methods are robust.”

Sometimes there is no admin data equivalent to draw on. The technical lead for the Data Iwi Leaders Group, Kirikowhai Mikaere, is concerned about the impact on iwi-affiliation data. “Census is the primary source of this data and we saw when the 2018 Census pivoted to admin data that iwi data was disproportionately affected.”

Kirikowhai Mikaere (Tūhourangi, Ngāti Whakaue) is the technical lead for the Data Iwi Leaders Group and Pou Ārahi of its operating arm, Te Kāhui Raraunga.

When asked if Stats NZ had enough of a “skeleton” to assemble iwi data from admin sources, Mikaere’s response was an emphatic “No”.

“I don’t know if we should rely on them to do this. It is important that we have it for the country. But I’m not sure they would have the trust from the communities to create the right skeleton for us.”

We must get it right.

Changing how the Census is done could impact what we know about New Zealand.

Cook stated that the Census is not just about the collection of data, it is about collecting data with scientific rigour. “We underestimate the extent to which we have co-ordinated the quality and standard of official statistics, compared to other data sources.” This rigour underpins our ability to use Census data, not only to understand how the population is structured but also how it changes over time.

Cook, with the University of Otago’s Public Health Communication Centre, has called on Stats NZ to be fully transparent about the scientific impact of changing Census models. Collecting the wrong data in 2028 not only creates the risk of using the data to make bad policy decisions, it also makes it harder to evaluate policies because we won’t know what has changed.

Mikaere echoed the importance of getting things right. “This is about the country having the right data to make informed decisions about a better future for our nation.”

Why engage with the consultation?

Mikaere: “I would really encourage people to engage with the consultation, not just to share their concerns, but it also is an opportunity to provide some innovative solutions. Your future mokopuna need you!”

Cook: “I have been an official statistician in two countries. I guarantee you government statisticians have no idea how all the official statistics are used.”

Sowden: “There’ll be ideas out there that we haven’t thought of, so come and tell us those it would be great to know.”

Notes

• Go here for the Modernising our approach to the 2028 Census consultation
• Current Census completion rates are interim rates. The official coverage rates will be published on December 9 this year.
• After his term as New Zealand Government Statistician, Len Cook was the National Statistician and Director of Britain’s Office for National Statistics.