Here is a real-time example of people “voting with their feet.” We lived in Puerto Rico from 1993 and 2009, and we can tell you that Puerto Ricans are severely overtaxed by their government, regardless of which political party is in power, and since citizens of Puerto Rico are also citizens of the United States, they are free to move to the U.S. without a passport. By the way, the full report about the decline in Puerto Rico’s population is here, via the Pew Research Center. In any case, what is the optimal level of population growth on a small Caribbean island (our home from 1993 to 2009)?