Beijing failed to report the widely-used Gini coefficient for income distribution for 12 years as complaints grew about the widening income gap during China's fastest growth on record.
It prompted suggestions the ruling Communist Party might be trying to downplay the gap between an elite who benefited from more than three decades of reform and the poor majority.
The Gini coefficient measures countries from zero to one, zero meaning there is perfect equality, and one equalling maximum inequality.
China's Gini coefficient was 0.474 last year on a 0-to-1 scale, down from a high of 0.491 in 2008, said the director of the National Bureau of Statistics, Ma Jiantang.
That would make China among the world's most unequal societies.
By comparison, Mr Ma said Brazil's Gini number was 0.55, Argentina's 0.46 and Russia's 0.40.
Mr Ma said: "On the one hand, we need to make the cake bigger, while on the other we need to do a better job of sharing it."
Narrowing the gap is a pressing issue for the new Communist Party leaders who took power in October.
China's boom has made multibillion-dollar fortunes for some entrepreneurs, but income growth for the majority has been sluggish.
Complaints about the lavish lifestyles of officials, Communist Party figures and military officers who drive luxury cars, own villas and send their children to elite foreign universities have fuelled tensions.
The government last issued a Gini number for 2000. Since then, Mr Ma's agency has said it knew too little about incomes of wealthy households to do a calculation.