The state's unemployment rate dropped more than a full percentage point last month, which should be good news in an economic crisis.
But a troubling development was behind the plunge: more than 56,000 Minnesotans stopped looking for work.
Economists define an unemployed person as one without a job but trying to find one, meaning that people who stop looking are no longer considered part of the overall workforce. Their exit was the chief reason Minnesota's unemployment rate fell to 6% in September from 7.4% in August.
"This is not an encouraging sign," said Steve Grove, commissioner of the Minnesota Department of Employment and Economic Development, which released the data Thursday. "It means there are folks who are for whatever reason getting discouraged about their job search."
The state had seen only a 10,000-person decline in the labor force from February to August until last month's drop of 56,299 people.
Minnesota's labor force participation rate, or the percentage of the working-age population that is either employed or is looking for work, fell by more than a percentage point to 68.4% last month, the lowest it has been since 1978.
Minnesota typically has one of the highest participation rates in the U.S. and it remained much higher than the national average, which was 61.4% in September.
"We're higher, but you never want to see that go down, especially at a time when there are a lot of firms that are hiring," Grove said.