Abstract: Through constructing an actuarial model,this paper studies the sustainability of the pension insurance coordination fund in government departments and public institutions.The findings of the measurement show that the expenditure of the coordination fund has an increasing tendency year by year from 2015 to 2050,but the tendency turns to decline year by year from 2051 to 2060.The expenditure of the coordination fund is much larger than its income,and the gap has been created since the beginning of the system.To lower the pension adjustment coefficient can effectively reduce the expenditures and improve the balance of the coordination fund.In the short term,the larger the contribution base,the larger the gap between the income and expenditure of the coordination fund and the heavier the burden.But in the long run,the larger the contribution base,the narrower the gap between income and expenditure of the coordination fund,which can effectively improve the balance of coordination fund.If the retirement age is delayed,the balance of coordination fund can be significantly improved.If the contribution rate of the units is lowered,the balance gap of coordination fund will be increased.Therefore,it is suggested that to raise funds from multiple sources and make up for the gap of the coordination fund in the same year,to establish a reasonable pension adjustment mechanism,to put into effect and appropriately increase the payment base,to introduce and implement the policy of delayed retirement age as soon as possible,not to lower the payment rate of pension insurance in government departments and public institutions,to bridge the use of the coordination fund with the personal account fund,and to turn the personal accounts into nominal accounts.

Key words: government departments and public institutions, pension insurance, coordinated fund, sustainable, actuarial balance