Investment income is the income received as a result of investing pension savings. Pension assets are managed by the National Bank of the Republic of Kazakhstan and private investment companies at the choice of the depositor. Pension savings are invested in various financial instruments (securities, foreign currencies, etc.), the value of which is constantly changing due to the economic situation in the world. Therefore, investment income can both increase and decrease. If you carefully look at the extract from the individual pension account, you can see that the amount of investment income is changing, and the amount of pension contributions actually made remains unchanged. The revaluation of the value of pension assets is carried out on a weekly basis as of the end of the first working day of the week and at the end of the last calendar day of the month. That is, the accrual of a "new" investment income can be tracked these days. It is important to emphasize that pension savings are long–term investments and it is advisable to analyze the amount of investment income for a period of at least one year. Short–term data (weekly, monthly, etc.) are not indicative, because they depend on constant current changes in market conditions.