The number of U.S. residents without health insurance soared to a record high last year as employment-based coverage plummeted, the U.S. Census Bureau reported last week.

The number of uninsured in 2009 hit a record 50.7 million, up from 46.3 million in 2008, while the percentage of U.S. residents without coverage climbed to 16.7% in 2009 from 15.4% a year earlier, the Census Bureau said.

Correspondingly, the number of people with health coverage dropped to 253.6 million last year from 255.1 million the previous year, which the Census Bureau said is the first time the number of insured declined since it began tracking health insurance coverage in 1987.

The percentage of people covered through employer-sponsored plans fell to 55.8% in 2009 from 58.5% in 2008, also a record low.

Conversely, the percentage of people covered through government programs increased, though that did not offset the decline in employment-based coverage.

For example, the percentage of the population covered by Medicaid—the federal-state program for the poor—rose to 15.7% in 2009, up from 14.1% the previous year; and the number of people enrolled in Medicaid jumped to 47.8 million from 42.6 million. Those figures also are records.

On the other hand, the percentage and number of people enrolled in Medicare remained nearly steady in 2009 vs. 2008. In 2009, 43.4 million people were enrolled in Medicare. That was 14.3% of the population, about the same as 2008.

The decline in employment-based coverage came amid the worst economic downturn since the Great Depression. The unemployment rate topped 10% in 2009, with millions of employees losing their health insurance coverage. While Congress last year passed legislation in which the government paid 65% of COBRA health insurance premiums for laid-off employees, not everyone could afford to pay 35% of the premium.

If the health care reform legislation Congress passed in March is successful, the uninsured rate could tumble. Federal researchers estimate that the law will bring coverage to more than 30 million uninsured U.S. residents, chiefly through an expansion of Medicaid and the establishment in 2014 of federal premium subsidies to the lower-income uninsured.

The Census Bureau’s report, “Income, Poverty and Health

Insurance Coverage in the United States: 2009,” is available at www.census.gov.