Calculate the accumulated value on balance subject to compound interest and outside changes, e.g. a loan or bank account.
Run python3 compound-interest-calculator.py
Then, answer the queries:
Principle: The initial value on the account.
Rate: The rate of the interest added per cycle (as a percentage).
Payments: The ammount by which the balance is reduced every cycle (before interest is applied). Use a negative value to increase the balance.
Number of Cycles: The number of cycles after which to calculate the accumulated sum.
See the document A Formula for the Computation of Compound Interest With Payments.pdf for the proof and derivation of this algorithm.