crear una tabla de amortización

function amortization($amount, $yearlyInterestRate, $termInYears)
{

    $monthlyInterestRate = $yearlyInterestRate / 1200;
    $numberOfPayments = $termInYears * 12;

    $monthlyPayment = $amount * ($monthlyInterestRate / (1 - pow(1 + $monthlyInterestRate, -$numberOfPayments)));

    $balance = $amount;
    $interest = 0;
    $principal = 0;

    $totalInterest = 0;
    $totalPrincipal = 0;

    echo "Payment # \tInterest \tPrincipal \tBalance";

    for ($i = 1; $i <= $numberOfPayments; $i++) {
        //calculate interest
        $interest = $monthlyInterestRate * $balance;

        //calculate principal
        $principal = $monthlyPayment - $interest;

        //deduct principal from remaining balance
        $balance -= $principal;

        //update totals
        $totalInterest += $interest;