Experience of the formation of pension systems in the leading countries of the world.

The pension system is composed of the elements that form a complex socio-economic system. Each system has its own characteristics and has its own experience of reform. At present the need for change in the pension system is related to the changing demographics (decrease in the number of employable population while increasing the number of pensioners). The article analyzes the emergence and development of pension systems in the most advanced countries, is considers international experience in building the systems of compulsory pension insurance and the classification of these systems. The analysis of the experience of formation of pension systems in the leading countries showed that the most modern pension systems were based on the principles of supply and solidarity, but in a changing demographic situation it was necessary to move to the notional accounts system. Bear in mind that the main goal of ongoing pension reforms in the leading countries is to achieve financial sustainability of these systems, while in the less developed countries (e.g. Ukraine) it is an issue of increasing the amount of pension benefits and ensure a decent standard of living for pensioners. Given the above, it seems appropriate to refer to the experience of the development of neighbouring countries to Ukraine for an objective analysis of the possibilities of using their experience in our country. The promising way out of the situation with pensions in Ukraine could consist in realization of the concept of "double dividend", which is a multi-disciplinary approach, as it proposes concurrent solution of the pension problems along with the urgent problems of environmental pollution. In the future in Ukraine private pension funds could become an attractive direction of provision of pension benefits for the part of the population that will be able to make financial savings.