St. Lawrence County has a rate of people without health insurance that is twice the overall rate in a region that Excellus Blue Cross Blue Shield defines as “upstate.”

On Thursday, Excellus released a statement touting a “historic level” of a 4 percent rate of people in upstate New York without health insurance. That number in St. Lawrence County is 8 percent, Excellus said.

Excellus includes 20 counties in their upstate region that go from the North Country to the Southern Tier. In addition to St. Lawrence, the region includes Broome, Cattaraugus, Cayuga, Chautauqua, Chemung, Clinton, Erie, Jefferson, Livingston, Madison, Monroe, Niagara, Oneida, Onondaga, Ontario, Oswego, Steuben, Tompkins and Wayne counties.

The New York state average is 6.1 percent, Excellus said.

The figures come from “an Excellus BlueCross BlueShield analysis of the U.S. Census Bureau’s 2017 American Community Survey.”

The American Community Survey is what the insurer describes as “the largest and the U.S. Census Bureau’s recommended source for examining uninsured data at national, state and regional levels.” It reports the yearly uninsured rate for geographic areas with populations of 65,000 or more. The county-level data were aggregated to calculate the upstate uninsured rate cited by the health plan, Excellus said.

“More people than ever before are reporting they have coverage that provides them with access to the high-quality health care available in upstate New York,” Christopher Booth, chief executive officer of Excellus BCBS, said in a prepared statement. “We’ve never seen these percentages of the population with coverage.

“We believe the historically low uninsured rates for upstate are a result of lower-cost health care in this market of nonprofit health plans and nonprofit hospital systems.”