<prompt> Human: Im 27 with 20K in my 401k. Lets say I put 10k in a year. By the time I retire at 65, my 401k is only 400k. Life expectancy is 75 ish so that means 40k a year for the rest of my life. Thats barely enough to live on as a healthy young person in 2017. How is that supposed to be reasonable in 50 years with inflation and massively increased health costs? Especially since social security likely wont exist. Edit: thanks for all the info guys! Looks like I am completely clueless. Ive got some research to do  <response>: You should be investing in the stock market, or some other securities that give you a return. The example you gave assumes no growth, which is not realistic unless youre just holding your retirement contributions in cash. The average real return of the stock market has been 7. Over 40 years, 10K a year you would end up with over 2 million. 