Definitions

Years to save: The number of years you have to save.
Savings goal: The amount you wish to have in savings at the end of this savings plan.
Amount currently saved: Total you currently have saved toward this savings goal.
Monthly savings: The amount you will contribute each month to your investments. This calculator also assumes that you make your contribution at the beginning of each month.
Expected rate of return: This is the annually compounded rate of return you expect from your investments. For the purposes of this calculator, taxation is not factored into the results. If you pay taxes on the interest, dividends or capital gains from these investments you may wish to enter your after tax rate of return.
The actual rate of return is largely dependent on the type of investments you select. From January 1970 to December 2007, the average compounded rate of return for the S&P 500, including reinvestment of dividends, was approximately 11.4% per year (source: www.standardandpoors.com). During this period, the highest 12-month return was 61%, and the lowest was -39%. Savings accounts at a bank pay as little as 1% or less.
It is important to remember that future rates of return can't be predicted with certainty and that investments that pay higher rates of return are subject to higher risk and volatility. The actual rate of return on investments can vary widely over time, especially for long-term investments. This includes the potential loss of principal on your investment. It is not possible to invest directly in an index and the compounded rate of return noted above does not reflect additional sales charges and fees that funds may charge.
Expected Inflation Rate: What you expect for the average long-term inflation rate. A common measure of inflation in the U.S. is the Consumer Price Index (CPI), which has a long-term average of 3.1% annually, from 1925 through 2007. The CPI for 2007 was 2.4%, as reported by the Minneapolis Federal Reserve.