There are a lot of factors to consider when it comes to retirement planning.  If you’ve ever plugged in assumptions on a retirement calculator to try to determine “your number” then you know what I’m talking about.  One thing you want to avoid underestimating is your average life expectancy.  This is a key number telling you how many years your retirement income will need to last.  You will need to take into consideration factors such as your family medical history, your current health, etc.  While people are generally living longer, your family history plays a primary role in how you should view your life expectancy.  Remember, if you live into your 90’s you may need to plan for a lower investment withdrawal rate over your golden years.