HWK Help: Loan Amortization

   
   #include <iostream.h>
   #include <math.h>
   #include <iomanip.h>
   
   int main (void)
   
   {
   
   //Declare Variables
   
   double principal, rate, mrate, mpay, factor, interest, balance;
   int month, cnt;
   
   //Program Title
   
   cout << endl;
   cout << "Loan Amortization Program\n";
   cout << endl;
   
   //Input from User
   
   cout << "What is the value of the loan? ";
   cin >> principal;
   
   cout << "What is the loan duration (in months)? ";
   cin >> month;
   
   cout << "What is the APR (Annual Percentage Rate)? ";
   cin >> rate;
   
   cout << endl;
   
   //Calculation of Monthly Payment
   
   mrate = (rate/1200);
   factor = pow( (mrate+1), (month));
   factor = (factor-1);
   mpay = (mrate+(mrate/factor))*principal;
   
   //Display Output to User
   
   cout << "Loan Amortization Information:\n";
   cout << endl;
   
   cout << "Intial Loan Value: $" << principal << "\n";
   cout << "Loan Duration: " << month << " months\n";
   cout << "Annual Percentage Rate: " << rate <<"%\n";
   cout << "Monthly Payment: $" << mpay << "\n";
   cout << endl;
   
   //Up to this point, everything works and is formatted correctly.
   
   //Loop for Displaying Monthly Information
   
   cout << "Month\t" << "Starting Balance\t" << "Interest\t" << "Payment\t"
   << "New Balance\t" << endl;
   
   cout << endl;
   
   cnt = 1;
   while (cnt <= (month-1))
        {
   	 interest = ((principal*(rate/100))/month);
   	 cout << setw(3); 
   	 cout << cnt << "  ";
   	 cout << setprecision(6);
   	 cout << principal << "  ";
   	 cout << setprecision(4);
   	 cout << interest << "  ";
   	 cout << setprecision(6);
   	 cout << mpay << "  ";
   	 cout << (principal = ((principal+interest)-mpay)) << endl;
   
   	cnt++;
   
        }
  
   //Problems to Correct:
   //Need to figure out why its not going to zero but very small decimal on last value of last month.
   //Decimal Points on the last one of the loop above go to 3 places,
   //and some only do one (i.e. 7.5 instead of 7.50),
   //while others do none (i.e. 8000 instead of 8000.00)
   
   
   interest = ((principal*(rate/100))/month);
   
   cout << setprecision(6);
   cout << month << " ";
   cout << principal << " ";
   cout << setprecision(4);
   cout << interest << " ";
   cout << mpay <<" ";
   cout << (principal+interest) << " ";
   cout << ((principal+interest)-mpay) << endl;
   
   
   cout << endl;
   return 0;
   
   }