NEW YORK — The Institute for Supply Management, formerly the Purchasing Management Association, began formally surveying its membership in 1931 to gauge business conditions.

The Creighton Economic Forecasting Group uses the same methodology as the national survey to consult supply managers and business leaders. Creighton University economics professor Ernie Goss oversees the report.

The overall index ranges between 0 and 100. Growth neutral is 50, and a figure greater than 50 indicates an expanding economy over the next three to six months.

Here are the state-by-state results of the April survey in the Mid-America region:

Arkansas: The overall index for Arkansas rose to 67.9 in April from 67.8 in March. Components of the index were new orders at 70.1, production or sales at 69.6, delivery lead time at 60.6, inventories at 66.0 and employment at 73.3. “Even without a rebound in construction and pullbacks among nondurable-goods manufacturers, the state’s economy continues to expand,” Goss said. “Job growth among durable-goods manufacturing has been restrained by increases in production from current employees and rising hours worked,” he said.

Iowa: For the 28th month in a row, Iowa’s overall index remained above growth neutral in April. The index slipped to 66.2 from March’s 67.5.  Components of the index were new orders at 69.0, production or sales at 65.7, delivery lead time at 55.7, employment at 70.9, and inventories at 69.8. Durable- and nondurable-goods manufacturers were adding jobs at a healthy pace, Goss said, and manufacturers tied to agriculture and dependent on foreign sales were experiencing especially strong growth. “As a result of this solid expansion,’ Goss said, “I expect Iowa’s unemployment rate to move below 5 percent for the first time since 2008 by the middle of 2012.”

Kansas: The state’s overall index rose to 56.4 in April from 55.3 in March. Components of the index were new orders at 53.3, production or sales at 63.1, delivery lead time at 53.5, employment at 57.8 and inventories at 54.3. Goss said manufacturers were benefiting from international sales. But, he said, manufacturing in aerospace and food processing was experiencing flat growth, if any. “In Kansas, we are seeing firms rely on new hiring rather than expanding the hours worked for their current employees,” Goss said.

Minnesota: The overall Minnesota index remained above growth neutral for the 32nd consecutive month. The index rose to 61.0, compared with 56.7 in March. Components of the index from the April were new orders at 71.1, production or sales at 69.5, delivery lead time at 55.2, inventories at 49.1 and employment at 60.2. “As in past months, durable-goods manufacturers, such as metal producers, are growing briskly even as nondurable(-goods) producers detail no gains,” Goss said. In addition to upturns in hiring, employers were increasing the work hours of their current employees, he said.

Missouri: The Missouri index rose to 60.2 last month from 58.3 in March. Components of April’s index were new orders at 64.3, production or sales at 60.9, delivery lead time at 55.9, inventories at 59.2 and employment at 60.8. “The state’s construction sector continues to weigh on the Missouri economy,” Goss said. But he said there were solid upturns in Missouri’s durable-goods manufacturing.

Nebraska: The state’s overall index remained above growth neutral for the 18th straight month. The index rose only slightly, to 53.5 in April from 53.0 in March. Components of the index were new orders at 52.4, production or sales at 53.9, delivery lead time at 54.9, inventories at 52.0 and employment at 54.3. Nebraska companies reported much slower but positive growth with few new hires and little change in the average workweek, Goss said. But he said durable-goods manufacturers continued to grow. “Based on our survey results, I expect Nebraska’s growth to slow but remain positive in the months ahead,” Goss said.

North Dakota: North Dakota’s overall index dipped to 62.7 in April from 63.0 in March. Components of the overall index were new orders at 61.3, production or sales at 58.6, delivery lead time at 62.8, employment at 74.2 and inventories at 56.8. “The gap between North Dakota’s growth and that of the region and the nation continues to widen,” Goss said. “Our surveys over the past several months indicate no change in that pattern as firms connected to agriculture and energy grow at very strong rates. Firms are not only adding to their payrolls, they are also increasing the hours worked for their current employees. I expect the average workweek among manufacturers in North Dakota to exceed that of every state in the region and nation,” he said.

Oklahoma: The state’s overall index jumped to 62.6 in April from 58.6 in March. Components of the leading economic indicator for April were new orders at 59.3, production or sales at 53.8, delivery lead time at 83.4, inventories at 54.0 and employment at 63.0. “Second only to North Dakota, Oklahoma’s growth continues uninterrupted and very positive,” Goss said. “Our survey indicates no change to that growth in the months ahead.  Despite healthy economic activity, firms in the state are not adding to the hourly workweek of current employees.  Instead, firms are adding new workers.”

South Dakota: South Dakota’s overall index slipped to 63.2 in April from 64.4 in March. Components of the index for April were new orders at 66.2, production or sales at 72.2, delivery lead time at 47.6, inventories at 68.4 and employment at 61.8. “Manufacturers in the state continue to expand employment and to increase the hours worked for current employees,” Goss said. Computer and electronic manufacturers in South Dakota were expanding, thanks to national and international sales, he said.