While the number of uninsured across the nation remained flat at 16.3 percent of the population, the number of Connecticut residents who lack health insurance increased slightly in 2010 to about 11 percent or 384,000, according to the latest U.S. Census numbers.

The overall number of uninsured residents in Connecticut jumped over the past few years from 309,000 in 2007-2008 to 385,500 in 2009-2010. The largest group of uninsured is under the age of 65.

Based on a comparison of two-year average rates people under age 65 who were without health insurance for the entire year rose from 10.3 percent in 2007-2008 to 12.5 percent in 2009-2010.

There was no statistically significant increase in the number of uninsured children. The state’s HUSKY health insurance program and the new federal health reform law that allowed children to remain on their parents insurance until the age of 26 are credited for helping to hold down the number of uninsured in that age group.

Census data indicates that an estimated 374,000 of all Connecticut residents under age 65 in 2010 were without health insurance for the entire previous year. Among Connecticut children under age 18, an estimated 49,000 lacked insurance for the entire year.

Only those at the time the U.S. Census was taken who didn’t have insurance for an entire year were counted in the survey.

According to an analysis of the data by Connecticut Voices for Children, there was also a statistically significant decline in the percentage of people under age 65 in Connecticut who had employer-based health insurance over this decade, dropping from 78.6 percent in 1999-2000 to 70.8 percent in 2009-2010.

There was a similar significant decrease in children who were covered by employer-based insurance – from 77.2 percent in 1999-2000 to 69.6 percent in 2009-2010.

“We need affordable coverage that is portable and not dependent on profit-margins so individuals and families no longer have gaps in their health care,” Juan A. Figueroa, president of Universal Health Care Foundation of Connecticut said in a press release. “Individuals and small businesses need more affordable choices, and as long as small businesses, the main engine for job growth…we cannot expect significant change in the number of the uninsured.“

“The problem is getting worse and 2014 won’t be soon enough for some of those businesses who are struggling right now,” Figueroa said.

In 2014 is the year the exchanges created under the federal Patient Protection and Affordable Act go into effect. The exchanges will be where everyone, including small businesses, purchase their insurance.

The board set up to create and facilitate Connecticut’s exchange will hold its first meeting 9 a.m. Thursday, Sept. 15.