NEW YORK – The income gap between rich and poor Americans grew to the widest in more than 40 years in 2011 as the poverty rate remained at almost a two-decade high.

The U.S. Census Bureau released figures Wednesday that showed median household income fell, underscoring a sputtering economic recovery and struggling middle class that are at the center of the presidential campaign.

The proportion of people living in poverty was 15 percent in 2011, little changed from 15.1 percent in 2010, while median household income dropped 1.5 percent. The 46.2 million people living in poverty remained at the highest level in the 53 years since the Census Bureau has been collecting that statistic.

“The gains from economic growth in 2011 were quite unevenly shared as household income fell in the middle and rose at the top,” said Robert Greenstein, president of the Center on Budget and Policy Priorities in Washington.

Average incomes fell for the bottom 80 percent of earners and rose for the top 20 percent, highlighting the need for “those at the top to share,” as the nation looks to reduce its budget deficit, Greenstein said.

The top 1 percent of households experienced about a 6 percent increase in income, said David Johnson, chief of the social, economic and housing division at the Census Bureau.

Isabel Sawhill, a senior fellow at the Brookings Institution in Washington who studies poverty issues, had projected the 2011 poverty rate would rise to 15.5 percent. She said the static number may be a result of unemployment benefits keeping thousands out of poverty.

The data also show the number of Americans who lack health insurance declined to 15.7 percent from 16.3 percent, as many under age 26 took advantage of a provision in Obama’s 2010 health-care overhaul that allowed them to be covered under their parents’ plans.

Median household income last year was $50,054.