The share of Connecticut residents living without health insurance is on the decline, according to a Census Bureau report.

The findings, part of a larger nationwide report on income, poverty and health insurance released last week, show that the number of uninsured in the state declined from 397,000 in 2010 to 303,000 in 2011, meaning that 8.6 percent of Connecticut’s population is currently uninsured. Largely a result of increased reliance on federal programs, the decline mirrors a national trend in which the overall proportion of uninsured people in the United States moved from 16.3 percent in 2010 to 15.7 percent of the population in 2011, bringing the total number of uninsured from 50 million to 48.5 million.

Most of the decrease in the number of U.S. uninsured is attributable to the fact that young adults can now remain on their parents’ health insurance plans until the age of 26, a key provision of the landmark Affordable Care Act passed in 2010. The law, also known as Obamacare, played a less significant role in Connecticut, where almost all young adults have been able to remain on their parents’ plans until 26 since the passage of a 2008 law. The drop in uninsured Connecticut residents is due primarily to an increase in the number of residents on Medicare and Medicaid.

As Connecticut continues to struggle with high unemployment, many residents have lost access to employer-based health coverage.

“Though we have seen some improvement, it does seem that some of the effects of the recession are still lingering on,” Census Bureau analyst Jennifer Day said.

According to the non-profit advocacy organization Connecticut Voices for Children, in 2000-’01, 78 percent of Connecticut residents under 65 had employer-based health coverage. By 2010-’11, that number declined to 69.8 percent.

In response to last week’s Census Bureau report, Connecticut Voices for Children attributed the relative steadiness of the number of uninsured to efforts made by state policy makers to expand access to Medicaid and Healthcare for UninSured Kids and Youth (HUSKY) — a Connecticut health insurance program for children, their parents, and pregnant women.

“Our administration’s goal is to make sure all children and adults in Connecticut have access to quality, affordable health coverage and care,” Lt. Gov. Nancy Wyman said. “Whether that coverage is offered through employers, a public program or the private marketplace, residents of our state have a variety of options to enroll in a medical plan.”

In New Haven, lack of insurance among children and pregnant women continues to be a problem, although the city has worked to guide those groups toward government resources.

“The city works hard to identify uninsured residents and to connect them to existing programs such as Medicaid,” City Hall spokeswoman Elizabeth Benton ’04 said, adding that the city “works with families to identify children eligible for Medicaid and to make sure they are properly enrolled and remain enrolled.”

The Affordable Care Act was signed into law in March 2010 and includes provisions that prevent insurers from denying coverage based on pre-existing conditions and a mandate that, beginning in January 2014, almost all Americans have health insurance.

MATTHEW LLOYD-THOMAS