人口の規模の違い difference in the size of the populations

人口の急減 rapid decrease in population

人口の急増 leap in population●rapid expansion of population●rapid increase in population

人口の急増〔~の〕 surge in one's population

人口の激増 population explosion

人口の顕著な増加 marked increase in population

人口の原理 principle of population 【著作】An Essay on the Principle of Population, As It Affects the Future Improvement of Society〔英1798《著》マルサス(Thomas Robert Malthus)〕

人口の減少 decline in population●population decline●reduction in the population

人口の減少した都市 depopulated city

人口の減少による経済的な損害を克服する overcome the economic harm from population decline

人口の高齢化 aging of the population●aging society●graying of society●graying of the population●increasing average age of the population

人口の高齢化に伴い as the population ages