Porto Rico has about ten times as many inhabitants per square acre as the average throughout the United States; but the conditions of climate do a great deal to equalize this difference. In the first place, the soil is available in Porto Rico for the production of crops throughout the twelve months of the year, whereas in parts of the United States and in northern Europe the soil is usable for only a portion of the year on account of its unproductive condition during the winter months. Another matter that must be taken into consideration in the question of overpopulation, is the severity of the climate. Where the climate is severe, the country will maintain in comfort a much smaller population than where the climate is as friendly to the human race as we find it in Porto Rico. Of the population of Porto Rico in 1910, about 75 per cent lived in communities that had less than 500 inhabitants, showing conclusively that the great majority of the people of Porto Rico should be classified as rural inhabitants and that the problems which affect the rural people of Porto Rico are the problems which would affect, to a great extent, the entire Island. Only two cities in the Island have a population of more than 25,000, while only 30 would fall under the head of urban territory, that is, towns which have a population of 2,500 or more. The rate of increase of population in Porto Rico is far in excess of the rate of increase in the United States, and this is one of the things that must be taken into consideration in considering the question of overpopulation. In the United States the rate of increase among the class of people whose salaries range from $700 to $2,500 is from ten to twelve per thousand. In Porto Rico, the rate of increase is about twenty per thousand. The following table shows a comparison between the birth rate, death rate, and rate of increase in the United States and Porto Rico, the figures given representing the birth and death rate for every thousand of the population in each country. UNITED STATES Birth rate Death rate Increase _Poor Class_: 35 to 40 25 to 35 5 to 10 _Intermediate class_: 25 to 30 15 to 18 10 to 12 _Well-to-do class_: 12 to 18 12 to 15 4 to 6 PORTO RICO (1914-15) Birth rate Death rate Increase 39.12 19.72 19 to 20 In order to maintain the population of a country, there must be about 400 children between the ages of one and five years for every thousand women between the ages of fifteen and forty-five. The following table shows how Porto Rico compares in this respect with other countries.