How to calculate compound interest using calculator?

monthly investment = 200, years = 40, interest rate = 8%
total value at end of investment period = 648,000

M = final amt including principal
P = principal
i = interest
n = no. of years invested

Formula: M = P (1+i)n

How can you do this using a calculator without having to calculate it each year? Sample below.

At start:

S = P

After 1 period:

S = P + Pr = P(1 + i)

Amount at the start of this period

Amount of interest earned during this period on the starting amount of this period

Final value at end of this period

After 2 periods:

S = P(1 + i) + P(1 + i)i = P(1 + i)(1 + i) = P(1 + i)2

Amount at the start of this period, i.e., the final value at the end of the last period

Amount of interest earned during this period on the starting amount of this period

Final value at end of this period

The easiest way is to buy a financial calculator which has all those formulas built in. It is difficult on a regular scientific calculator.

Here is the formula.
S = P(1 + r/k)^n
S Final value of investment
P Initial value of investment
r Annual percentage rate (APR)
k Interest periods per year
r/k Percentage rate per interest period
n Number of interest periods
*

I give you best answer for explaining it. My HP12 does it as well.

Give yourself best answer, because im not sure I can find a question. I only see an answer.

You have been answered many definitions, here is an online calculator

http://www.discountingcashflow.com