The state's health insurance exchange is reminding a subset of individual market shoppers that they still have a week to buy 2017 coverage.

It's a message that has added urgency since health insurers say the state's individual market is shrinking.

"Thousands of Minnesotans not insured for 2017 still qualify for a special enrollment period (SEP) if they or someone in their household lost 'qualifying health insurance' in the past 60 days," MNsure said in a Wednesday statement. "This includes Blue Cross and Blue Shield customers and HealthPartners customers living in Greater Minnesota."

MNsure is an option for people who buy individual health plans, which cover those who are self-employed or don't get benefits from an employer or government program.

Last year, about 100,000 people in the individual market were covered by health plans that were eliminated in their counties by Eagan-based Blue Cross or, to a lesser extent, Bloomington-based HealthPartners.

Some of those subscribers already have switched to new health plans for 2017. Those who haven't can still enroll in 2017 coverage via a special enrollment period that ends March 1.

People in discontinued plans accounted for more than one-third of Minnesota's individual market last year, and insurers worry that some of those subscribers have simply stayed out of coverage entirely this year. That's a problem for the market, because it suggests healthy people who don't generate many medical bills aren't contributing premium dollars that offset the cost of those with serious and expensive conditions.

Earlier this month, the trade group for health plans in the state announced that the individual market is about 30 percent smaller than it was one year ago.

MNsure is a government-run health exchange created under the federal Affordable Care Act (ACA), which is driving fundamental changes across the individual market.

More Minnesotans bought 2017 coverage through MNsure than ever before, so they could tap federal tax credits to offset premium spikes.

But MNsure's growth hasn't offset the overall market decline, insurers said, with the number of people with individual plans dropping from about 270,000 people one year ago to 190,000 people this month.

It's not clear yet what's happening within individual market enrollment in other states, said Cynthia Cox, a researcher with the Kaiser Family Foundation. Nationally, enrollment in individual policies through health exchanges for 2017 is about 12.2 million people, down about 4 percent from 12.7 million in 2016, according to an analysis of data provided by the foundation.

But Cox said she's not aware of any state besides Minnesota where insurers have released numbers for the "off-exchange" enrollment, meaning individual health plans purchased directly from insurers rather than through a government-run exchange.

A report last year from the consulting firm Mark Farrah Associates estimated about 7.5 million people across the country — roughly 37 percent of the overall individual market — were enrolled in off-exchange policies.

Christopher Snowbeck • 612-673-4744

Twitter: @chrissnowbeck