Chile's government has been advised to annul its 2012 census because it failed to account for nearly 10% of the country's population.
An independent panel said census takers failed to count more than one million people because they were not at home or homes were wrongly labelled as empty. It recommends holding another census with fewer questions in 2015.
President Sebastian Pinera has been meeting government advisers to decide whether to accept their advice, the BBC reports.
"The commission believes that the 2012 census suffers from serious problems,'' the experts said in their report, commissioned by the National Statistics Institute.
The commission said the government surveyed 15.8 million people, when it should have been closer to 17.4 million.
It blamed the problems on Mr Pinera's government but also said that problems during the administration of former President Michelle Bachelet delayed the census.
The 2012 census cost about $US32 million, according to Mariana Alcerreca, a former senior officer at the statistics institute.