Thomson Reuters

The economy lifted more Americans from poverty in 2018 but failed to drive broader economic progress across households.

Median incomes were essentially flat after three years of growth last year, the Census Bureau said in a report Tuesday.

The median household income was $63,179 last year, statistically unchanged from 2017 and near where it stood in 1999.

The figures suggested rising inequality has continued to undermine progress during the longest expansion on record.

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The longest expansion on record lifted more Americans from poverty in 2018 but failed to drive broader economic progress across households, whose incomes were essentially flat after three years of growth.

The Census Bureau said in a report out Tuesday the poverty rate fell to 11.8%, its lowest level since 2001 and significantly below levels seen during the global financial crisis. But the median household income was $63,179 last year, statistically unchanged from 2017 and near where it stood two decades ago.

"Median household income today is right where it was in 1999," Justin Wolfers, an economist at the University of Michigan, wrote in a tweet on Tuesday. "Two decades with no progress for the middle class."

While the figures reflected the stagnant pattern median income has moved toward over recent decades, average income continued to grow last year. That suggests rising inequality is a central issue holding back the middle-class, according to Wolfers.

"The gains from economic growth are not being broadly shared," Wolfers told Markets Insider over email, adding that a $1.5 trillion tax-cut package that took effect last year could further widen the gap between the rich and the poor. "And these are pre-tax numbers. The Trump tax cuts obviously did more to exacerbate post-tax inequality."

The share of Americans without health insurance rose to 8.5% last year for the first time since the Affordable Care Act was expanded in 2010, the Census Bureau report showed. Democrats said the increase to 27.5 million without coverage was fueled by the Tax Cuts and Jobs Act passed in 2017, which removed a penalty for those who don't have health insurance.

This all came despite a continuation of the decade-long expansion. Last year saw historically low unemployment rates, which would typically put upward pressure on wages.

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