The modern processes of globalization showed crisis aspects in development of financial relations. Financial crises started covering the whole global economic society, which leads to fluctuations in the balance of the whole economic system. In such situation, it is important to determine the reasons for instability and to develop the methods for preventing crisis situations. Analysis of foreign and domestic studies on the problems of cyclicity shows that despite the large scientific progress, there is no integrated approach to determining the nature and essence of cyclicity of economic systems. The modern market economy is peculiar for susceptibility to changes and structural instability. Using classic methods of forecasting of economic dynamics is difficult - thus, there's a necessity to develop the methods that allow forecasting the dynamics of economic cycles and diagnosing crisis situations at the initial stages of development. Thus, the purpose of the work is to develop one-product dynamic model "bank's economy in the regime of bankruptcy", which allows for objective evaluation of the economic state of the bank in each period of time and for forecasting of bank's bankruptcy. The main provisions of the model are provisions of the Keynes theory of effective demand. Mathematical tools are based on the provisions of the theory of sustainability of elastic systems and differential equations of free fluctuations of non-conservative system. As a result, high-quality analysis of the model as to the values of bankruptcy indicator is given. This expands the possibility of operative management and forecasting of bank's economic state.
