By Paul Overberg and Janet Adamy 

President-elect Joe Biden is inheriting a country with an aging population that is on shakier economic footing and is more politically polarized than at most points in recent years.

Key metrics of financial and social well-being show the challenges Mr. Biden faces as he moves into the White House on Wednesday. The coronavirus pandemic halted the 11-year economic expansion and drove up unemployment just as the typical American household was starting to enjoy sustained income growth. Americans were living longer -- an improvement from a period when the opioid crisis eroded life expectancy -- until the pandemic exacted a swift, deadly toll. One government official said life expectancy could decline by the largest amount since World War II once the government completes last year's mortality figures.

Long-running demographic trends also have shaped the country. The U.S. is becoming more racially diverse. More Americans are obtaining college degrees. Women are having fewer babies, and the population is growing at its lowest rate in over a century.

After stagnating in the wake of the 2007-09 recession, America's earnings gradually improved starting around the middle of the last decade. Median household income was $68,700 in 2019, up 6.8% from the prior year and the highest figure on record. The poverty rate that year dipped to its lowest level since the government began tracking it in 1959. Last year's figures are expected to show disparities in whose incomes suffered, with some households being better off because of stimulus payments and extra unemployment benefits.

The stock market has marched to near-record highs, lifting the net worth of investors while leaving behind the nearly one half of Americans who don't own stock. Consumer debt has climbed as families have borrowed more heavily to stay in the middle class.

Joblessness was at a half-century low before the pandemic forced businesses to close their doors temporarily, and in some cases permanently, starting in March. The U.S. economy shed 9.4 million jobs last year, the most in any year since records began in 1939, and nearly double the number from 2009.

The U.S. debt as compared with the size of the economy reached its highest point since the end of World War II, after government spending to combat the fallout from the virus rose sharply and tax revenue fell.

An uptick in drug deaths and suicides began shortening U.S. life expectancy midway through the last decade. That metric was starting to improve until Covid-19 emerged last year to become the nation's third leading cause of death, according to early estimates from Robert Anderson, chief of the mortality-statistics branch of the CDC's National Center for Health Statistics.

Kenneth M. Johnson, a demographer at the University of New Hampshire, estimates that the pandemic will cause deaths to outpace births in more than half of U.S. counties in 2020 for the first time in U.S. history. Between 2010 and 2020, the number of people over age 55 grew by 27%, while the population under 55 grew at a rate of 1.3%, according to estimates from the Brookings Institution.

Another historical first is that the country's non-Hispanic white population shrunk toward the end of the last decade. The number of Hispanics, Blacks and Asians in the U.S. continues to grow, and the fastest-growing demographic is people of two or more races.

The share of noncitizens dropped steadily, falling below half of all immigrants, as arrivals slowed under tighter controls and as a steady stream of immigrants became citizens -- almost three-quarters of a million a year.

After growing during the 2007-09 recession, the number of America's uninsured began shrinking once the 2010 Affordable Care Act took effect. The law subsidized private insurance coverage for low and middle earners and gave states money to expand the Medicaid insurance program for the poor. Those gains began to erode during the Trump administration, when the number of Americans without health insurance coverage at some point during the year rose for the first time in a decade.

The share of Americans who identify as conservative or liberal hasn't changed much over the past decade. But within the parties, there has been a slight movement toward the more ardent corners of each ideology. Among GOP registered voters, 37% identified as very conservative in 2020, up from 33% in 2010, according to Wall Street Journal polling. Among Democratic registered voters, 25% considered themselves very liberal in 2020, up from 16% in 2010.

In terms of geographic mobility, Americans were relocating at one of the lowest rates on record at the end of the last decade. In recent years, the population growth of large metropolitan suburbs and small metropolitan areas has outpaced the growth in urban cores and sparsely populated parts of the country.

Write to Paul Overberg at paul.overberg@wsj.com and Janet Adamy at janet.adamy@wsj.com

(END) Dow Jones Newswires

January 20, 2021 09:56 ET (14:56 GMT)

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