Michigan Economy Improves in December, Reports Comerica Bank's Michigan Economic Activity Index

DALLAS, March 8, 2012 /PRNewswire/ -- Comerica Bank's Michigan Economic Activity Index rose two points in December, up to a level of 91.  The December index level is 31 points, or 52 percent, above the index cyclical low of 60. The index averaged 91 points in 2011, seven points above...