You are currently age 35, and you want to retire at age 67. you currently have saved $20,000 for retirement. You want to withdraw an annual amount, starting the day you retire, that will have the same purchasing power as $50,000 has today. Assuming an average reture on your investment of 7.5% annually, and an average inflation rate of 3.5% annually, how much must you save each year until retirement to meet your goal?