The latest survey of Supply Managers in a nine state region of the Midwest and Plains shows many have hope for a rebound yet this year, even as the survey’s other indices show the coronavirus pandemic has knocked the economy in middle America for a loop. The Mid-American business conditions index released Friday plummeted from March’s 46.7 to 35.1 in April. The lowest reading since February 2009. But the Confidence Index, which gauges Supply Manager’s Economic Outlook for the next six months, rose to 45.5 from March’s record low 14.5. Any score above 50 suggests economic growth, while scores below 50 suggest decline