A car that has been modified to transport specialized goods. When the economy overheats and inflation rises, interest rates are raised and credit tightened. When the overheated economy and inflation are under control, the interest rate is duly lowered. Interest rates are therefore one of the fundamental economic factors. Interest rates are an important financial variable in economics, and almost all financial phenomena and financial assets have more or less connection with interest rates. Planning is so important for the success of the transaction that it is necessary to use a hypothetical example to further illustrate.