Household incomes are outpacing wage growth because millions of Americans have returned to the work force, a vivid illustration of the old maxim that a job is the best antipoverty program. The economy added roughly 2.2 million jobs last year and an additional 1.4 million in the first eight months of this year.

The Census Bureau report is the second in a row to find strong income growth. A year ago, the bureau reported that the median income in 2015 had risen by 5.2 percent, the largest jump since record keeping began in 1967. The 2016 gains described on Tuesday pushed the median to the highest level on record, topping the previous peak in 1999.



But Census Bureau officials cautioned that those figures were not directly comparable because of a change in its methodology in 2013 that has tended to increase measured incomes.

The Economic Policy Institute, a liberal research organization based in Washington, estimated that without the change in methodology, median household income in 2016 was still 2.4 percent lower than in 1999 — and 1.6 percent below the level reached in 2007, before the recession began.

The Census Bureau report also pointed out continuing challenges, including income inequality. The average household income for the poorest fifth of households fell by $571 over the decade that ended last year, adjusting for inflation. Over the same period, the average income for the wealthiest fifth of households rose by $13,479, adjusting for inflation.

Racial disparities also have increased. The bureau reported that the median income for African-American households has fallen by 1.6 percent since 1999. The adjusted numbers provided by the Economic Policy Institute pegged the drop at 7.5 percent.

The annual report is based on a survey of 95,000 households.

“Just as in 2015, 2016 is going on record as another year of massive income inequality,” said Mary Coleman, senior vice president at Economic Mobility Pathways, a Boston nonprofit group that focuses on female and family poverty. “There was no meaningful reduction in income inequality.”