Manitoba Finance Minister Jennifer Howard has said the 2011 flood, one of the largest in the province's history, contributed to inaccurate population figures.
Since federal transfer payments are based on population, the discrepancy translates into a loss of $100 million a year, she said, and could make it impossible to fulfil the government's promise to balance the books by 2016.
Jane Badets, a director general with Statistics Canada, said Manitoba actually had one of the highest response rates in Canada in the 2011 census. Still, the agency expects to miss a certain number of people in each census, she added.
Statistics Canada uses a complex methodology to make up for any people who might be missed — something Badets said was agreed to by all provinces including Manitoba. Using that system, the agency actually added almost 22,000 people to Manitoba's population in 2011.
"We had a good response rate in Manitoba," Badets said. "We do miss some. We know that. It's no different than any other census. We use the same methods we've ever used.
"We worked with the provinces and territories. They understand the methods. They agreed to it. They approve it."
Howard said she's not interested in getting into a "methodological argument" with Statistics Canada. The province knows its population is growing at a faster rate than the agency has acknowledged, she said.
"It's counter to what we know in terms of the number of people filing taxes in Manitoba. That's gone up at a higher rate than StatsCan is saying the census has. There is an error here and we need it to be corrected.
"This could be that one-in-20 rogue sample that is off. Let's redo it and see what the results are."
Finance Department officials' calculations of a $100-million shortfall a year are based on transfer payments for health care, social services and equalization. Manitoba is already losing $37 million in this fiscal year, Howard said.
The minister suggested it may take spending cuts in health care and education in the province to still balance the books in 2016.
"Losing $100 million because our population has been undercounted, that makes it challenging to do that without cutting spending in those areas or looking at how we balance the budget."
Critics are questioning the government's figures and the timing of its complaint.
Opposition Leader Brian Pallister said the 2011 census figures have been out for months, but the NDP government waited until now to raise the issue. The complaint also comes after a provincial sales tax increase which came into effect in the summer, he said.
"This is a provincial government — the only provincial government — that has a dispute over the ability of the federal government to count people. Nine others don't," the Conservative leader said.
"Coincidentally, this is the same provincial government that actually jacked up taxes by a record amount."
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