HELP
 
 
http://www.vertex42.com/Calculators/annuity-calculator.html © 2009-2016 Vertex42 LLC
About This Template  
This annuity calculator is based on general finance theory. It is designed to simulate a case where a person makes regular withdrawals from an account that is earning interest. It also allows you to enter an annual inflation rate to simulate the case where the person increases the amount that they withdraw each period (to keep up with rising expenses for example).
Taxes: This spreadsheet does not account for taxes. Iinterest is assumed to be earned tax free. To get around that, you could try entering a tax-adjusted interest rate (e.g. if you're in a 25% tax bracket, subtract 25% from the expected Annual Interest Rate). Payouts represent pre-tax withdrawals. So, if you are receiving payments from a Roth IRA, you wouldn't pay tax, but if you are receiving payments from a Traditional IRA, you would. 
TIP: Use Excel's built-in Goal Seek utility (Data > What-If Analysis > Goal Seek) to answer the following question:
What does the Starting Principal need to be if I want a payout of 2000 per Month?
Additional Help  
The link at the top of this worksheet will take you to the web page on vertex42.com that talks about this template.
  REFERENCES  
SEE ALSO Vertex42.com: Loan Amortization Schedule
SEE ALSO Vertex42.com: Personal Budget Spreadsheet
TIPS Vertex42.com: Spreadsheet Tips Workbook