Optimization methods for individual’s bank deposit amount considering the requirements of Russian tax legislation

The subject of the study is methodological tools of financial calculations related to individual time deposit amount optimization under the requirements of Russian tax legislation. The purpose of the study is to develop a mathematical model that contributes to improving the level of validity of an individual’s investment decisions, allowing optimizing the amount of a bank deposit with the option of interest capitalization and controlling the tax burden on individuals’ income from deposits. As a result of the study, a mathematical model for calculating the initial deposit amount for a savings account was developed and tested. This model will allow depositors to determine the maximum amount to be placed in the account without exceeding the limits of tax-free income. The study relied on theoretical level scientific methods such as abstraction, deduction and formalization. These methods enabled a focus on a particular methodological technique of investment management, the essence of which is to optimize the deposit amount, taking into account the key parameters: the annual interest rate, the limit of tax-exempt income, and term of money deposit. The proposed mathematical model is adapted to the conditions of monthly capitalization. The practical significance of the presented model is determined by its application as an element of the methodological tools of investment and financial management. It can be associated not only with the optimization of the bank deposit amount of an individual considering the requirements of the national tax legislation, but also in rational investment behavior and personal finance management.