As Richard Florida shows, looking at income in this way has a leveling effect:
"As anyone who has ever paid Manhattan rents swiftly learns, New York City's relatively high salaries don't go very far. In fact, when cost of living is taken into account, the New York metro posts the second lowest "real income" of any region with more than 500,000 people, according to an analysis commissioned by US News and World Report. New York's median household income of $62,887 falls to an adjusted real income of just $35,370 when cost of living is taken into account. Only the McAllen-Edinburg-Mission metro in Texas, one of the very poorest in the nation with an actual income of just $30,460, fares worse with a real income of $34,931."