Research On The Balance Of Income And Expenditure Of Individual Pension Account Under Stochastic Interest Rate

Pension has always been a people’s livelihood issue of concern.With the development of science and technology,the improvement of medical level and the acceleration of population aging process,the problems faced by China’s basic pension insurance are gradually emerging.As an important part of the whole old-age insurance system,the old-age insurance for urban residents has a large gap in the fund and can not maintain balance of revenue and expenditure due to the high bookkeeping interest rate,low actual rate of return and unadjusted monthly balance sheet for many years.In China’s latest planning outline,it is also pointed out that we should gradually implement the policy of delaying the retirement age,appropriately increase the minimum payment period,revise parametric adjustment measures such as the number of months for the calculation and issuance of employees’ pension insurance personal accounts,and strive to achieve the goal of pension insurance system reform.Firstly,under the policy background of delaying the retirement age,this paper refers to the relevant literature at home and abroad,combined with the relevant theoretical knowledge such as interest theory,life table theory and stochastic process theory,and constructs the calculation and payment months and substitution rate model of pension personal account under fixed interest rate from the perspective of balance of payments and sustainable development of payment.Based on the perspective of gender differences,the parameters are set according to China’s relevant policies and actual situation.Through numerical analysis,the number of months and replacement rate of pension personal account under fixed interest rate are calculated,and the corresponding adjustment conclusions are given.Secondly,considering the randomness of interest rate change in financial market and the limitation of fixed interest rate,CIR random interest rate model is introduced,and the weighted least square estimation method is used to estimate the parameters.In order to further eliminate the ARCH effect,the CIR-GARCH model is constructed.Combined with Eviews8 software,the improved model parameters are estimated,and the calculation and payment months and substitution rate model of individual pension account under random interest rate are constructed.Finally,through the numerical analysis of Monte Carlo simulation method,the empirical function distribution of the number of months and substitution rate of pension personal account under random interest rate is simulated,and the corresponding parameter adjustment conclusions are given.Compared with the numerical analysis results of the number of months and substitution rate of the individual pension account under the fixed interest rate,the parameter adjustment conclusion more in line with the actual situation of the individual pension account is obtained,which provides reference suggestions for further promoting the reform of the pension insurance system.