OMAHA, Neb. (AP) — A monthly economic index for nine Midwestern and Plains states hit a three-year high in April, suggesting more economic growth over the next three to six months, according to a report issued Thursday.

The overall Mid-America Business Conditions Index rose to 60.4 from 58.2 in March.

“Much like the national economy, the Mid-America region continues to expand with growth prospects improving monthly. This is the highest overall reading that we have recorded since March 2011,” said Ernie Goss, director of Creighton University’s Economic Forecasting Group, who oversees the report.

The survey results from supply managers are compiled into a collection of indexes ranging from zero to 100. Survey organizers say any score above 50 suggests growth, while a score below that suggests decline. The survey covers Arkansas, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma and South Dakota.

Looking six months ahead, the business confidence portion of the overall index jumped to 64.2 in April from 59.0 in March.

“Improvements in the job market supported supply managers’ business outlook for the month,” Goss said. “Furthermore, some of the uncertainty surrounding the number of signups for the Affordable Care Act has been reduced, thus boosting confidence.”

The supply managers last month were asked to gauge the impact of the implementation of the health overall on their companies. Almost two-thirds, or 65.5 percent, reported little or no impact; 3.6 percent reported a significant negative impact; and 29.8 percent reported a negative impact. Just 1.2 percent reported a positive impact from the act.

After declining below growth neutral for December, the employment index has remained above the threshold for fourth straight months. It dipped slightly in April, to 54.2 from 54.4 in March.

“Durable-goods manufacturers, including vehicle producers, and nondurable-goods producers, such as food processors, are adding jobs at a healthy pace,” Goss said. “There are more workers employed in the nine-state region than ever. I expect current growth to continue in the months ahead,” he said.

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