The simulation uses four scenarios of population aging and briefly analyses the most likely of them. It uses the number of people of each age and average government’s revenues and expenditures related to citizen of every year of age to calculate total revenues and expenditures for 2013 to 2100. The simulation identifies 2060 to be the most problematic year with the deficit over 11% of GDP. The paper concludes that without increase in labor productivity the population’s ageing leads to the collapse of public finances. At the same time only a slight increase in labor productivity is sufficient to keep the actual level of pensions and budget balanced in the long run.