The Density of Smart People - Creative Class
San Francisco and New York are far and away the leaders in human capital density with 7,031 and 6,357 college degree holders per square mile, respectively. Boston (3,871), Washington, D.C. (3,395) , Seattle (2,853), and Chicago (2.543) all have human capital densities in the range of 2,500 to 3,500 degree holders per quarter mile. Silicon Valley has a human capital density of 1,259 degree holders per square mile.
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Stats on density of college graduates per square mile in different American cities.