We find that fertility has been declining since 1974 in Japan. Fertility rate becomes below 2.00 and it will be probably reported 1.79 in 1978. This trend can be also found in Europe and the United States, especially West-Germany recently. As it's fertility rate was 1.45 in 1975, West-Germany can't keep replacement level of population under the existing conditions. Demographers and others are mostly interested in the estimation of future population and analyzing causes of declining fertility. When we try to estimate future population in Japan under it's fertility rate equal to 1.45, we can get several important results. (1) The maximum of population will be 122 million in 2000. (2) If it decreases after 2000, population will be equal to 110 million (population in 1975) until 2020. (3) Both birth and death rates will be about 10 per thousand in 2000. (4) The speed of aging of population will be accelerated, and then one of five persons will become the old above 65 years old in 2015. (5) At the same time, there will be population above 70 years old more than that below 14 years old. Demographers pick up some causes effect on declining fertility in Japan. It is illustrated that increase of investment in education makes parents had children less than two. And the diffusion of family-planning contributed greatly to birth control. On the other hand, we can find mobility transition, changes of mobility patterns as a recent population phenomenon. The mobility from rural to metropolitan areas has been a main stream until 1965 in Japan. But there are multiple streams, channels of mobility recently. Population redistribution will be continued and accelerated in the future. There are differences of fertility forces among areas. Generally the fertility rate of urban area is lower and rural area is contrary. We are greatly interested in what effect the redistribution has on the trend of fertility. It's the problem what migrants from urban to rural behave themselves concerning their reproduction.
In this article I have viewed the workers' quit propensities in the United States. Specifically I have analyzed the factors influencing quit rate variation among industries in terms of the monopoly and competitive dichotomy. In order to do this I have performed regression analysis of quit rate variation among industries after dichotomizing the sample of 110 industries into monopoly and competitive sectors. The model I used regressed the quit rate for each industry (Yq) on the wage (Xw), concentration ratio (Xc), expansion ratio (Xe), ratio of female workers to all employees (Xf), and the ratio of production workers to all employees (Xp). The result of the statistical analysis indicates some essential difference between monopoly and competitive industries in terms of the workers' quit propensities and in terms of the factors influencing their quit behavior. The quit rate tends to be high in competitive industries, and the wage, low. The wage is the most important explanatory variable for quit rate variation in competitive industries. These aspects of evidence indicate that in competitive industries, workers are quitting more frequently than in monopoly industries, and that their motives are better wages elsewhere. These findings suggest that the traditional free market principle still functions in the labor market of this sector of the economy. In high concentrated industries, on the other hand, workers do not quit frequently, and when they do, the wage is not the sole motive. As shown by the strong correlation between the quit rate and the concentration ratio, there are certain aspects of concentrated industries, in addition to high wages, which make workers reluctant to quit. If we reflect these findings on the features of the employment system of monopoly firms, the analysis verifies that monopoly industries offer high wages and also incentives other than wage which make workers want to stay with the firm.