Your parents will retire in 20 years. They currently have $450,000 saved, and they think they will need $1,000,000 at retirement. What annual rate of return must they earn to reach their goal, assuming that they don't save additional funds? Provide answer in percentage format without using the %sign. Round your final answer to 2 decimal places. To be marked correct, the answer provided needs to be +/- 0.01 from the actual answer.