Prediction Of Optimal Retirement Age Under Dynamic Mortality

In recent years,with the continuous improvement of medical service level and quality of life,life expectancy has increased year by year.However,due to the pressure of life,the vast majority of young people choose to marry at a later age,which leads to the increasingly prominent problem of population aging in China and seriously affects the stability of the pension system.The introduction of the delayed retirement policy is helpful to increase pension income,reduce costs,and ease the pressure on pension balance,which is of great significance to maintaining the sustainability of China’s current pay-as-you-go account.At present,most scholars have analyzed the impact of delayed retirement policy on China’s pension pooling account from two macro perspectives: the advantages and sustainability of delayed retirement policy.However,the micro-individuals,that is,individual workers,who are closely related to the policy of delayed retirement will have an impact on the utility level and pension wealth of workers.For workers,while implementing the policy of delaying retirement,they will give priority to optimizing personal utility level and wealth value of the elderly.Therefore,setting a reasonable retirement age is of great significance.This paper discusses the relationship between life expectancy and the optimal retirement age from two aspects: the utility of workers and the level of personal endowment wealth.To some extent,it makes up for the deficiency of micro-research on longevity risk,and explains the necessity of delaying retirement policy.The existing research only obtains the optimal retirement age by setting different life expectancy parameters,which does not reflect the completeness and rigor of the data.In this paper,from the point of view of the individual utility of workers in the whole working cycle and the maximization of individual pension wealth,the effective parameters and influencing factors in the current pension system are adopted,and the relevant dynamic actuarial model is established by Bayesian MCMC.The mortality rates of different sexes in all ages in China from 1995 to 2019 were collected,and the remaining life of workers was divided into three stages,from the entry age to before the statutory retirement age,before and after the statutory retirement age.The mortality rate was predicted by winbugs software,and the life expectancy of men and women in the next 20 years and the probability of the three stages were obtained.Then,by substituting the life expectancy and the three-stage mortality rate into the actuarial model,the optimal retirement of men and women with different life expectancy could be obtained by calculation.The numerical simulation method is used to calculate the impact of delayed retirement policy on personal utility and personal pension wealth,quantitatively analyze the factors that determine the level of personal pension wealth and the changing trend of personal utility,and analyze the sensitivity of the influencing factors.Stata software is used to make regression analysis on life expectancy and optimal retirement age under different conditions,verify the significance and authenticity of the model and influencing factors,then adjust the current statutory retirement age,study and formulate reasonable and feasible schemes to achieve the effect of delaying retirement age,scientifically and effectively evaluate the effect of delaying retirement policy,and provide basis for relevant policy formulation,which has practical significance and theoretical value for research in this field.The results show that the optimal retirement age is positively correlated with life expectancy,economic growth rate and employment age,and negatively correlated with the years of pension.Among them,life expectancy has the greatest influence on the optimal retirement age,and the differences between men and women in the optimal retirement age are also very different.Therefore,relevant government units should fully consider the influencing factors,respect the interests of different workers,openly and clearly define the relationship between working hours and pension income,improve the flexibility of workers’ choice of retirement time,reduce the resistance to the reform of retirement system,and finally play an important role in the delayed retirement policy.In the future,we will continue to study on this basis,and fully consider the dynamic changes of inflation rate and account interest rate,the influence of personal preference on utility level,and the influence of the difference of personal pension contribution ratio and wage level on personal pension wealth and personal utility.The model in this paper sets the above parameters to fixed values,which can’t fully reflect the influence degree of dynamic changes of parameters.Therefore,the follow-up research will gradually improve the dynamic analysis of the above parameters.Secondly,in the future research of actuarial model,factors such as basic old-age insurance rate and social basic old-age insurance fund comprehensive account balance will be considered,and to some extent,the influence of these parameters on the significance and accuracy of actuarial model will be discussed.