47) According to Dissimilarity-Index scores, disparities in health care density are no longer
evidence of core-periphery inequality.
48) In the United States, the percentage of the population living in urban areas peaked around
1920.
49) In 2000, 32 countries in the core had rates of natural increase of 0.0 or less. That means that
at this rate their populations will never double.
50) It is impossible for a country to have a negative rate of natural increase.
51) In 2014, Indonesia (pop. 251 million), Mexico (pop. 120 million) and El Salvador (pop. 6.4
million) all had rates of natural increases of 1.4. This means their populations are projected to
double at the same time.