As a teenager, Enrique learned a valuable lesson from his dad, who told him to invest $1,000 at 8 percent interest at age 20 and leave the money alone until age 65. Enrique's dad knew that one strategy used by wealthy people is to exercise self-discipline and never touch a long-term savings plan. Enrique is happy to apply his dad's advice. If his savings account earns a more aggressive 14 percent annual rate of return, Enrique's savings will be worth approximately ________ more by age 68.