SALT LAKE CITY -- Census figures show that 388,000 people in Utah don't have health insurance.

Those figures include about 100,000 more people than state agencies have estimated and 40,000 more than advocates for the uninsured have forecast in the worst-case scenario.

Census figures released Wednesday showed that Daggett County has the highest percentage of uninsured residents at 27 percent and Carbon County has the lowest at 12 percent.

Nationwide, nearly 47 million people are uninsured.

"This is the most extensive look ever at county-level demographic characteristics of people with and without health insurance coverage," said Lynn Blewett, director of the Census Bureau's State Health Access Data Assistance Center in Minneapolis. "Despite some minor data shortcomings, this provides unprecedented information on how health insurance coverage varies [from] county to county and state to state."

At least 20 states, including Utah, are looking into how they can provide more-affordable health care. "Enhancing both access and quality ourselves will be a much better solution than anything that is imposed," said Utah House Majority Leader David Clark, R-Santa Clara. "And becoming part of that effort at this stage is as open to the single mom who can't find coverage [as] to the business owner trying to cover employees in the face of double-digit insurance premiums."

Comprehensive health insurance premiums in Utah have risen nearly 70 percent since 1999, or about 9 percent each year, according to the state Department of Health. The number of Utahns who have coverage has declined 13 percent since then.