# mortgage.py
principal = 500000.0
rate = 0.05
payment = 2684.11
total_paid = 0.0
month = 0
extra_payment = 1000.0
extra_payment_start_month = 61
extra_payment_end_month = 108
while principal > 0:
month = month + 1
principal = principal * (1+rate/12) - payment
total_paid = total_paid + payment
if month >= extra_payment_start_month and month <= extra_payment_end_month:
principal = principal - extra_payment
total_paid = total_paid + extra_payment
print(month, round(total_paid,2), round(principal, 2))
print('Total paid', round(total_paid, 2))
print('Months', month)