Those factory shutdowns will further erode an industrial workforce that has been shrinking as a share of the overall U.S. economy for decades. While manufacturing output last year surpassed a previous peak from 2007, factory employment never returned to levels reached before the financial crisis. Michigan Maple Block Co. furloughed most of its 56 workers at its plant in Petoskey, Mich., when the state implemented a stay-at-home order on March 24. A month later, the manufacturer of cutting boards and industrial table tops told employees the plant would close for good. A second factory in Pennsylvania will remain open because of cheaper energy costs, said Ann Dau Conway, president of the company that her family has owned for generations. “The hardest decision of my life. Not just my professional life,” Ms. Conway said. The closures suggest that a growing share of the record job losses in recent weeks won’t […]