Kathy deposits $500 into an investment account with an annual rate of 1.5%, compounded annually. The amount in her account can be determined by the formula A = P(1 + R)^t, where P is the amount deposited, R is the annual interest rate, and t is the number of years the money is invested. If she makes no other deposits or withdrawals, how many years, to the nearest tenth, will it take for her money to double in value?