Madison has the ninth strongest economy in the U.S., according to Policom Corp.â??s 2010 rankings. The survey examines 23 measures of economic strength over a 20-year period. Data from 1989 to 2008 involving 366 metropolitan statistical areas was considered for the latest report. “While most communities have slowed or declined during this recession, the strongest areas have been able to weather the storm,” said William Fruth, president of Policom, based in Palm City, Fla. Madison has a diversified job base, with the state capital, UW-Madison, and employment strength in insurance, finance, technology and meat processing, Fruth said.