OMAHA, Neb. (AP) — The economy remains strong in nine Midwest and Plains states, but business leaders are concerned about the ongoing trade disputes, according to a new monthly survey released Monday.

The overall economic index for the region slipped to 57.5 in September from August's 61.1, but it remained in positive territory.

Creighton University economist Ernie Goss, who oversees the survey, said he expects business will slow but continue growing in the next few months because of the trade concerns and rising interest rates.

"I expect expanding tariffs, trade restrictions, and rising short-term interest rates from a more aggressive Federal Reserve, to slow regional growth to a more modest but still positive pace in the months ahead," Goss said.

The survey results are compiled into a collection of indexes ranging from zero to 100. Any score above 50 suggests growth, while a score below that suggests a decline, according to survey organizers.

The survey covers Arkansas, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, and South Dakota.

Even with the trade tensions, Goss said business leaders remain fairly optimistic because profits have been strong. The survey's confidence index jumped to 68 in September from August's 60.8.

Business costs continue to increase. The survey's inflation index remained high at 76.1 in September even though it declined slightly from August's 80.5.

The survey showed strong trading numbers, but Goss said that might be the result of some businesses buying in advance of new tariffs and trade restrictions.

The export index grew to 53.1 in September from August's 51.8. The import index decreased slightly to 57.2 from August's 58.1.

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