Since 1987, the share of the population in Medicaid has doubled.

In 2013, U.S. employers may have cut the number of people in their medical plans to 169 million – down from a peak of 179 million in 2008, and the lowest level recorded since 1997.

Enrollment in employment-based health plans seem to have fallen as use of individual health insurance and Medicaid jumped. The 2013 figures include some of the effects of the new Patient Protection and Affordable Care Act (PPACA) public exchange and Medicaid expansion programs on use of health insurance, and they may also include the effects of employer efforts to respond to PPACA changes and changes in the economy.

The Census Bureau reported the latest health insurance figures in a new report on the state of health insurance coverage in 2013. The bureau based the 2013 numbers on Current Population Survey polling conducted earlier this year. Bureau officials say they have redesigned their survey program. They cut historical data out of their latest report and have warned users to be careful about comparing the new data with the old data.

A comparison with the 2012 report shows that the size of the U.S. population increased to 313.4 million in 2013, from 311.1 million. The percentage of people without any health insurance dropped to 13.4 percent, from 15.7 percent in 2012, and the number of uninsured people fell to 42 million, from 48 million.

The percentage of people with what the bureau calls “employer-based coverage” fell to 53.9 percent, from 54. 9 percent. The employer plan share data in the 2012 report goes back to 1987. If the 2013 drop reflects a real change, not just a side effect of changes in survey methods, the percentage of Americans in employer plans is at its lowest level since at least 1987.

The percentage of people with “direct purchase” health insurance, or private individual health insurance, increased to 11 percent, from 9.8 percent, and the number with individual coverage increased to 34.5 million, from 30.5 million. The percentage of Americans with individual coverage was over 11 percent in the early 1990s, but the number of people with private individual health coverage is the highest the Census Bureau has recorded since 1978, according to data compiled by a predecessor of America’s Health Insurance Plans (AHIP).

Medicaid covered 17.3 percent of Americans in 2013, up from 16.4 percent in 2012, and the number of Medicaid enrollees increased to 54 million, from 51 million. Medicaid is bigger than it has ever been before. In 1987, Medicaid covered just 8.4 percent of the U.S. population.