The Prime Minister has had to throw Statistics New Zealand a lifeline, pumping in more money after Census results were delayed twice.
But those who work with vulnerable groups are still concerned holes in the data could mean funding doesn't get to those who need it most.
After going digital, just one in seven people took part in the survey of all New Zealanders.
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- Simon Bridges 'losing faith' in official statistics
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The delay was partly due to a lower than expected response rate - leaving data gaps to be plugged with other Government records.
Not all data holes can be plugged. The next Census results won't include iwi affiliation, which was used during Treaty of Waitangi settlement processes.
"Tens of thousands of households, many of whom are poor, many of whom are Māori and Pacific Island, will mean those people don't really necessarily get the funding that they should," says Child Poverty Action Group co-convenor Alan Johnson.
On Monday, the Government announced more cash for statisticians to help - an extra $5.76 million this Budget, followed by another $10.36 million for the 2023 Census.
But the Opposition is not convinced.
"Because we don't have accurate data, that means some areas where people really need more money and more support won't be able to get the money they want," says National MP Jian Yang.
The first tranche of Census information will be released in September, including the number of general and Maori electorates.
An independent review looking at how the Census failed to reach so many people is due in July.