Study On The Economic Effects Of Changing Population Age Structure Of China

To research on population changes of age structure on the economic effects of China has two means:first, it is helpful to answer the question that the demographic transition of China is quite different from western countries, because it is pushed by the family planning policy, are the demographic dividend of China consistent with the general rule of the effects of population transition on economic growth? It has important academic values; second, it is also helpful to understand the possible risks and benefits during the post demographic dividend in China for the first demographic dividend has been got, and to takes measurements to avoid the risks of the second demographic debt, and to gain the another demographic dividend called second demographic dividend or the derived demographic dividend, and that has direct policy implications and practical meaning.Based on the demographic transition theory, life cycle hypothesis of saving and neoclassical economic growth theory, the paper uses the concepts of the effective producers and the effective consumers, and makes use of the sample survey data in 2002, estimates the life cycle model of labor income and consumption across different age distribution of China. According to this age specific economic life cycle mode and National Transfer Accounts Manual, the paper uses the support ratio to macro-simulate the demographic dividend of China during different times from 1953-2005, and estimates its contribution to economic growth. Furthermore, the paper deduces the possible risks and favorable factors in the post demographic dividend.Some new ideas have been got from this paper just as follows:Firstly, the paper estimates the pattern of China's age specific labor income——consumption of economic life cycle both for urban and rural in 2002. There are 35 surplus years for average person when his labor income is larger than his consumption which from 23 to 58 years old. And it shows that both labor income and consumption expenditure in urban are higher than that in rural significantly, and the surplus age groups covered in rural are more wider that that in urban areas, it is confirmed that there are urban-rural income - consumption distortions existed which caused by dual structure. At the same time, the age specific labor income——consumption of economic life cycle pattern has proved that people at different ages have quite different labor productivity, i.e., the labor forces are heterogeneous.Secondly, the estimation method of first demographic dividend has been improved. It is common to use the value of dependency ratio to estimate the duration of the demographic dividend, this paper uses concepts of the effective producer and the effective consumers and the support ratio to estimate. More than 50 years long population and economic historical statistical data of China and the 2050 population projections data have been used, to estimate the effects of population age change on economic growth during 1953-2005. This method reduces the estimated error of the demographic dividend, and raises the explanatory power of demographic dividend theory of the real economic and social society. The result shows that the first demographic dividend was for more than 40 years long, and has began from the beginning of 1970s and will ended in 2015, so it is only a short time to be left for favorable for economic growth, after that time, there will turn to be the demographic debt.Finally, the new concept of post demographic dividend is proposed. The paper defines the concept of post demographic dividend clearly, and expands the research perspective from two-dimensional of the relationship between population and economic development to three-dimensional view of the relationship among population, economy, resources and ecological environment, and systematical analysis of possible unfavorable factors of China's population production and reproduction, environment and ecology production and reproduction, and economic development and sustainable development in post demographic dividend, some strategic thoughts of how to get rid of are proposed.