Saving, income, compound interest rate, ending savings, withdraw calculator

This saving & withdrawal calculator helps answer the questions for example:

If I have $5,000 in savings now and save $500 every month, with an annual rate of return of 8%, what is the calculated expected savings at the end of 20 years?
If I have $5,000 in savings now, with an annual rate of return of 8%, how much should I save every month to become a millionaire (with ending savings of $1 million) at the end of 20 years?
(Phase 2) How much money can I withdraw monthly from these savings for 40 years until they run out?

Phase 1
Current savings
Future monthly savings
Savings for	years
Annual investment yield
Max yield suggested The suggested max annual investment yield, based on the investment horizon, for the most aggressive investors. For conservative investors, the yield input should be lower than this.
Ending savings
	Make ending zero

Phase 2
Beginning savings
Future monthly savings
Savings for	years
Annual investment yield
Max yield suggested The suggested max annual investment yield, based on the investment horizon, for the most aggressive investors. For conservative investors, the yield input should be lower than this.
Ending savings
	Make ending zero