An office building rents for $40,000 the first year, then increases by 0.5% each year. Use summation notation to represent the total payments for the first three years. Explain your reasoning. Marcus’s response is given below: If rent increases by 0.5% each year, the year’s rent is 1.005 times the previous year’s rent. So, an exponential expression can be used. The summation is 1.005 raised to the year times $40,000, where the years go from 0 to 3.