The Power of Tax-Deferred Growth Why are 401(k) plans, annuities, and IRAs so popular? Share | Related Content 18 Years’ Worth of Days The average retirement lasts for 18 years, with many lasting even longer. Will you fill your post-retirement days with purpose? Conquering Retirement Challenges for Women Looking ahead can help you conquer these unique obstacles. A Look at Systematic Withdrawals This calculator may help you estimate how long funds may last given regular withdrawals.