Source: US Census Bureau and Fortune Magazine.
Corporate headquarters tend to be located in metropolitan areas that are well-integrated into air transport networks. Conversely, airlines tend to select their hubs based on the level of corporate activity. Among the many advantages of a well-connected airport city is the availability of direct flights to a large number of locations, which is highly advantageous for business trips. The above graph relates the number of Fortune 1000 headquarters to the metro population for 2006. Surveys found that 50% of Fortune 500 headquarters were located within 10 miles of a hub airport. This figure climbs to 84% at 20 miles.
In general, more populous metropolitan areas have more headquarters. The blue line is the regression line of best fit. Points above the line (positive residuals) have more headquarters than we would expect based on their population. Cities with a large hub operation for one of the big US carriers (American, United, Delta, Northwest, and US Airways) tend to have a sizable population and number of headquarters.