Calculate the effect of compounding interestand inflation on buying power in "Today's money" over a given number of years. This wil help you eveluate your savings and investment plan. It will note the years from now when you could expect to retire with your current lifestyle. This will be when 3% your net worth is equal or more then your current net income after mortgage payment. Assuming this will be payed off by then, otherwise the remaining mortgage is also added to the net income the 3% needs to match. Note that this only applies when your yield is more then 3%!