This is the book to focus on a new phenomenon emerging in the twenty-first century: the rapidly
aging and decreasing population of a well-developed country namely Japan. The meaning of this
phenomenon has been successfully clarified as the possible historical consequence of the
demographic transition from high birth and death rates to low ones. Japan has entered the
post-demographic transitional phase and will be the fastest-shrinking society in the world
leading other Asian countries that are experiencing the same drastic changes. The author used
the historical statistics compiled by the Statistic Bureau Ministry of Internal Affairs and
Communications in 2006 and population projections for released in 2012 by the National
Institute of Population and Social Security Research to show the past and future development
of the dependency ratio from 1891 to 2060. Then utilizing the population life table and net
reproduction rate the effects of increasing life expectancy and declining fertility on the
dependency ratio were observed separately. Finally the historical relationships among women's
survival rates at reproductive age the theoretical fertility rate to maintain the replacement
level and the recorded total fertility rate (TFR) were analyzed. Historical observation showed
TFR adapting to the theoretical level of fertility with a certain time lag and corresponding to
women's survival rates at reproductive age. Women's increasing lifespan and survival rates
could have influenced decision making to minimize the risk of childbearing. Even if the
theoretical fertility rate meets the replacement level women's views of minimizing the risk
may remain unchanged because for women the cost-benefit imbalance in childbearing is still too
high in Japan. Based on the findings the author discusses the sustainability of Japanese
society in relation to national finances social security reform family policies immigration
policies and communitypolices.
