50 biggest U.S. cities ranked by the geographic diversity of their populations

According to seattletimes.com Among the 50 biggest U.S. cities, Seattle ranks No. 3 on the “geographic diversity index” with a score of 79.3 Here’s what that means:
If you were to compare any two Seattleites at random, there’s about a 79 percent chance they were born in different areas of the country or the world.
The two cities ranked ahead of us are Las Vegas, followed by Colorado Springs, Colo.