Marc Perry, chief of the Population Distribution Branch of the Census Bureau appeared on C-SPAN to discuss the population shifts and demographics of the most populous cities in America.  In 2010, there were 33 cities with 500,000 people or more, up from 29 in 2000.  In the past decade, Fort Worth experienced the greatest growth, with a 38.6% increase in population.   With a nearly 25 percent decrease in population, Detroit fell outside of the top ten most populous cities, replaced by San Jose, CA.  Most of the cities with the largest percentage increase are in the South or the West; these regions underwent a much greater population boom than the Northeast and Midwest.  Major population shifts however appear to be in decline.  From 1983 to 2011, the geographical mobility index has steadily dropped, falling to almost half of what it was in 1983.  So while population growth in these urban centers is still steadily increasing, the migration between large cities is falling significantly.