Data from the latest U.S. Census illustrates the transformation of formerly predominant blue-collar cities into tech center hubs. For example, in historically industrial Boston, just 14.7 percent of the population is engaged in a job that requires manual labor. Census data also shows a rise in blue-collar jobs in unlikely cities such as San Jose, which has the second ?highest concentration of manufacturing jobs in the nation.
See "Tech jobs transform once blue-collar cities", Bill Briggs, USA Today, September 8, 2013