This application will allow you to forecast your capital accumlation over any time period up to 40 years. It will take your monthly contributions plus the rate of return on your capital and also the inflation rate into consideration. This is especially useful for people who are investing in a work savings plans such as a 401K. It assumes you know your monthly deposit rate, plus the rate of return and volatility of your capital assets. This information can be obtained from this return and risk calculator. The volatility is measured by the standard deviation of the asset or portfolio. The defaults below assume you will retire in 10 years time, you're starting with $100,000, getting a rate of return of 7% with an annual risk level of 7%. Inflation is set at 2.5% with a volatility of 1.5% and you're contributing $2,500 every month. The default simulation is run 25 times. The R code used for the simulation is available here.