<?php

error_reporting(-1);

$creditBalance = 40000;
$percent = 1.03;
$servicePayment = 1000;
$payment = 5000;
$paymentTotal = 0;

for ($month = 1; $month < 99; $month++) {
	$creditBalance = $creditBalance + $servicePayment;
	if ($creditBalance <= 0) {
		echo "Долг уплачен.";
		break;
	}
	if ($creditBalance < $payment) {
		$payment = ($creditBalance * $percent) + ($servicePayment);
	}
	$creditBalance = ($creditBalance * $percent) - $payment;
	$paymentTotal = $paymentTotal + $payment;
	echo "Прошло месяцев оплаты = $month \n Долг на текущий месяц = $creditBalance \n Уплачено = $paymentTotal \n";
}