New Zealand's population has officially grown to 4,699,755.
The number of Kiwis living here has jumped 457,707 since the previous census five years ago - the largest population growth by number since the 1961 census.
Population growth was at 2.1% since 2013, compared to just 0.7% for the previous Census period.
The biggest population growth was in the Queenstown-Lakes District, followed by Selwyn.
Queenstown-Lakes grew by an average of 6.8% per year between 2013 and 2018.
Dunedin in comparison grew by an average of 1% per year.
Central Otago grew by an average of 3.8%, Waitaki 1.4%, Clutha .9%, Southland .8%, Gore .6% and Invercargill 2.1%.
On the back of the data, the North Island will get one new electorate for next year's election, Stats NZ has announced.
Meanwhile, an independent panel considering the quality the data has found the low turnout could affect information about ethnic communities, local authorities and service providers.
The Government's statistics department has faced scrutiny since last year's Census – the first to prioritise online data collection - produced one of the worst participation rates in decades, with one in seven people failing to complete it.
That meant Stats NZ had to use alternative data from other Government agencies – such as birth records and drivers' licences - to fill the gaps.
On Monday, the department released the first set of data its put together from the Census, concluding there will need to be a new electorate somewhere in the North Island for next year's general election.
That will take the number of electoral seats from 71 to 72 (48 to 49 in the North Island), and decrease the number of list seats available in Parliament from 49 to 48.
There were no changes to the number of South Island or Māori electorates.
Where the new seat will go will be determined by a separate Representation Commission by April next year. After the last census an extra seat was added in Auckland with the Waitakere electoral being dissolved and new ones created in Kelston and Upper Harbour.
About a third of electorates will see their boundaries redrawn due to population shifts.
Key population figures release on Monday include:
• the North Island's population grew 10.9% from the 2013 census to 3,180,037
• the South Island's population increased 9.7% to 1,047,321
• Nationally, there was no change to the top five ethnic groups from 2013 to 2018 – NZ European (64.1%) Māori (16.5%) Chinese (4.9%) Indian (4.7%) and Samoan (3.9%)
• The percentage of the population born in New Zealand dropped from 74.8% in 2013 to 72.6%.
Stats NZ's general manager census Kathy Connolly says population could hit 5 million next year.
So how good was the data?
Stats NZ set up an independent panel of experts to assess whether the quality of the data produced in the Census is up to scratch.
In its first report, also released on Monday, the panel concluded that by using alternative Government data, the quality of the data had improved
It said in particular, using data from other agencies meant that groups that were usually under-counted in the Census – such as Māori and Pasifika populations – would be better represented.
And it said counts of Māori population for electoral purposes met the bar.
However, it raised questions about the quality of the Government's ethnicity data, refusing to accept it was "high quality" instead describing it as "moderate".
"The panel has taken a broader view of the needs of users of ethnicity data than simply the ethnicity variable itself," it said.
It said analyses of many population groups important to the government, including ethnic communities, local authorities, Māori and service providers, would be affected by the low response rate to Census questions.
Data relating people to dwellings would also be incomplete, with about 8% of the population unable to be placed in a specific home, the panel found.
A second report will be published by the end of the year.
With ODT
