Take a look at http://www.tonymarston.net/php-mysql/amortise.html which documents the loan amortisation program which I wrote in PHP. You can run it online and even download the source code to run it locally. -- Tony Marston http://www.tonymarston.net http://www.radicore.org "Ray Hauge" <ray.hauge@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:200609191000.07573.ray.hauge@xxxxxxxxxxxxxxxxxxxxxxxxxx > Hello everyone, > > This is a tad off-topic, but I'm at my wits end. I'm working on a loan > calculator for our load advisors to give an estimated monthly payment. We > had one, but it was really bad (gave horribly wrong information) and I've > had > to re-write it. The particular question about this loan calculator is on > a > graduated repayment type. This is where the loan pretty much starts off > paying only interest and then increases the payments by a certain > percentage > (graduation factor) every time the rate increase is supposed to happen > (graduation term)... which is usually two years. > > I've looked all over google, wikipedia, and I've even called our servicers > (who you'd think would help you out, but instead they just tell you they > can't give me those calculations). I have found a few other calculators > online that do this sort of thing, but I can't exactly see the source code > that way ;) > > This seems like a somewhat standard calculation for loans and interest > bearing > accounts. Does anyone know how to calculate the graduation factor? I've > been > able to figure out it's based off the loan term, loan balance, and initial > interest rate. > > Example: > $30,000 balance > 6% initial interest rate > 20 year loan term > > with those variables you would get a graduation factor of 6.95% > > So, the first payment would be $166.53, and then after the graduation term > (2 > years) the payment would increase to $178.10, then two years later > increase > again, and so on. That differnce in payment is pretty close to the > graduation factor. It's probably off due to the rounding. > > Thanks for placating me when grasping for straws ;) > > -- > Ray Hauge > Programmer/Systems Administrator > American Student Loan Services > www.americanstudentloan.com > 1.800.575.1099 -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
