Retirement is a marathon, not a sprint. According to Forbes, the average expected length of retirement is about 19 years for males and 21 years for females, assuming retirement at age 65. But 1 in 10 retirees live to see their 95th birthdays, and that proportion is likely to grow as medical screening and treatment improves. Planning for retirement is a marathon, too. You need to start early enough—and stay disciplined enough—to ensure that you have ample savings and income after hanging up your hat for good. Avoiding these five common retirement myths can help you beat the odds and…