International Comparison Research Of Population Dependency Ratio And Economic Changes

The population dependency ratio is an important indicator to measure the changes in the age structure of the population.The increase in the dependency ratio has a wide and deep impact on the macro economy,including income,consumption,savings,economic growth,and the micro impact including family structure,child education,oldage support.China’s demographic changes have provided the economy with demographic dividends for more than 30 years.The decline in the fertility rate brought about by the birth control policy has led to a rapid decline in the proportion of children,forming a period of abundant labor resources.However,the transformation of China’s demographic structure is faster than common sense.Since 2012,both the number and the proportion of working-age people has begun to decrease.and China’s economy is facing the dilemma of “getting old before getting rich”.The problem of changing age structure will become an important factor restricting China’s development.Based on Demographic Transition,Life Cycle and Neoclassical Economic Growth theory,using the dependency ratio and GDP data of 9 countries in the World Bank open data,this study first anchor three key factors for cross-sectional analysis,namely,a single country,per capita GDP and dependency ratio,and use two speed indicators to analyze the economic speed of population transition,which are the economic growth rate and the growth acceleration.Secondly,the similarity of time series between the dependency ratio and per capita GDP of the nine countries in this study is calculated by Dynamic Time Warping algorithm.The main conclusions of this study are as follows:(1)Some countries have grasped Demographic Dividend brought about by the demographic transition earlier and have begun to develop rapidly,while the economic transition of some countries has lagged behind their population.South Korea and Indonesia started to accelerate their economic growth when the child dependency ratio declined.The economies of China,India,and Brazil are slower than the transition of the child dependency ratio and the old age dependency ratio,and their growth is slow.USA began to grow rapidly at a lower oldage dependency ratio than UK and Germany.(2)The relative economic growth and acceleration of different countries are different.UK,USA,Germany,and Japan have seen small changes in their child dependency ratios,and their relative economic growth has been relatively fast.They have also maintained a relatively fast development momentum in the near future.Their old-age dependency ratio has changed significantly,and their economic growth rate has maintained fast and stable after reversing to a high level in the early stage until the level of 40,000-50,000 US dollars.The recent acceleration momentum is weak.The economic growth of South Korea,Brazil and Japan is not high and has shown a certain decline recently.(3)Judging from the similarity of the dependency ratio change curve,India,Indonesia and Brazil,UK and Germany,China and South Korea have high similarities which means similar patterns of change,while USA and Japan show certain uniqueness.From the perspective of the similarity of the change curve of per capita GDP,UK,Germany,USA,and Japan are highly similar.China,India,and Indonesia are similar.While South Korea and Brazil show certain uniqueness.(4)China’s old-age dependency ratio experienced a bigger change than developing countries,while it’s relative economic growth rate is very low.The acceleration of China’s economy relative to the old-age dependency ratio is very high,but the momentum has been insufficient in recent 3 years.China’s child dependency ratio has a relatively high rate of change,while the relative economic growth rate is relatively low.(5)The demographic transition in Japan is faster than the economy.The relative economic growth rate and acceleration are at the lowest level among developed countries,and the recent growth acceleration momentum is also the weakest.