The new Small Area Health Insurance Estimates released yesterday showed a little more than 11 percent of county residents went without health insurance that year, and most of them were living well below the poverty line.

The estimates also include insurance data for each state and county with residents aged 65 and younger. The 2005 data is broken down further by age, income, race and gender, making it the first time the Census Bureau has published extensive estimates on the uninsured.

Next year, these estimates will be included in the American Community Survey and single-year estimates also will be available for locations with populations of 65,000 or more, officials said.

Overall, Maryland has 4.2 million insured residents aged 65 years or younger. But there are also 728,630 uninsured residents, making up 15 percent of the population. Texas had the highest percentage of uninsured residents - 26.3 percent - while Minnesota had the lowest, with 9.5 percent.

Maryland health advocates said the numbers are troubling, but took relief in the state's efforts to turn those numbers around. Last year, lawmakers passed a five-year, $2.4 billion health plan that would extend coverage to more than 120,000 uninsured Marylanders.

"We've made some good progress over the last year and a half ... but this is not enough," said Vincent DeMarco, president of the Maryland Citizens' Health Initiative. "We're going to build on the success to achieve health care for all Maryland residents by making sure small businesses can afford health care."

Charles County had 11 percent of its residents lacking health insurance, the lowest percentage in the state. Anne Arundel County was not far behind, with 49,817 uninsured residents, or 11.3 percent of its population.

Twenty percent of Prince George's County's residents were uninsured in 2005, giving it the largest percentage in the state. Yet Worcester, Talbot and Kent counties followed closely behind, with populations greater than 19 percent.

With Anne Arundel County's uninsured population, about 32,000 of them lived in households where the income was at or below 250 percent of the federal poverty level. Queen Anne's County had nearly 6,000 uninsured residents in that time period, or 14 percent of its population.

Of the uninsured, about 3,800 residents were living below the poverty line.

Anne Arundel County Department of Health officials said they were concerned about these numbers, but continued to offer the Residents Access to a Coalition of Health (REACH) program. Roughly 1,500 county residents are involved in the effort, which is the result of a partnership between community doctors and health care providers.

Residents who meet income guidelines are assigned a case manager, then get referred to a primary care physician for services that range from $20 to $35, officials said. The program is open to residents aged 19 to 64.

"Basically, we are considered a safety net for the county residents who do not have access to health care or who do not have insurance," said Nan Bellini, REACH program supervisor. "We are not an insurance program, but we do provide an affordable way to access quality health care in the community."