[LAB 4] Loan payment

void setup()
{
  size(600,700);
  loan_Payment(1);
}

float loan_Payment(int year)
{
  background(0);
  int mouth = year*12;
  float money = 5000;
  float percent = 0.12/mouth;
  float interest = percent * money;
  float principal = 0;
  float total_Interest = 0;
  int startMouth = 1;
  float remain_money = money;
  float remain_principal ;
  text("NO"+"       "+"Interest"+"       "+"Principal"+"       "+"Unpaid Balance"+"       "+"total interest to date",width/6,height/14);
  principal = money * (percent/(1-pow(1+percent,-mouth))) ;
  remain_principal = principal;
  while(startMouth <= mouth)
  {
    total_Interest += interest ;
    remain_principal = principal - interest ;
    remain_money -= remain_principal ;
    interest = remain_money * percent ;
    text(nf(startMouth,2)+"          "+nf(interest,2,2)+"         "+nf(remain_principal,3,2)+"               "+nf(remain_money,4,2)+"                     "+nf(total_Interest,3,2),width/6,(startMouth*50)+height/14);
    startMouth++;
  }
    if(remain_money <= 0)
    {
      remain_money = 0;
    }
    return total_Interest;
}