(Reuters) - One day after announcing that income inequality increased in Brazil last year, the Brazilian statistics institute IBGE said on Friday it had miscalculated and issued a new number reversing the trend.
The correction is good news for President Dilma Rousseff, who is campaigning for re-election next month on her leftist government's record of improving social conditions in Brazil, but it left others wondering what was behind the revision.
The IBGE's annual households study released on Thursday said the Gini coefficient, a measure of income inequality, rose from 0.496 in 2012 to 0.498 in 2013, where zero is maximum equality and 1 is total income concentration.
The IBGE corrected the number to 0.495, saying it had made a methodological error. The agency denied the government had a hand in the change.
"There was no political pressure. It'd be surrealistic if we announced statistics and then changed them under pressure," IBGE research director Roberto Olinto said at a news conference.
But Rousseff's opponents, who are seeking to end 12 years of rule by the Workers' Party, were not convinced.
Centrist candidate Aecio Neves said the government was so anxious to stay in power that it was putting pressure on the statisticians to deliver positive data.
"The government is undermining the credibility of our most serious and respected institutions," he said in a statement.
The original data showing inequality rising made newspaper headlines and was an embarrassment for Rousseff, whose re-election is threatened by popular environmentalist Marina Silva in a race that is too close to call.
The Planning Ministry announced the creation of a commission of independent experts to look into what happened.