Show Annual Expenses

<!--Write a PHP script AnnualExpenses.php that receives n years from an input HTML form and creates a table with random expenses by months and the corresponding years (n years back). For example, if N is 10, create a table that shows the expenses for each month for the last 10 years. Add a "Total" column at the end, showing the total expenses for the same year. The random expenses in the table should be in the range [0…999]. Styling the page is optional.-->

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8"/>
    <title>Show Annual Expenses</title>
    <style type="text/css">
        table, th, td {
            border: 1px solid #000;
        }
    </style>
</head>
<body>
<form method="post">
    <p>
        <label for="number-years">Enter number of years:</label>
        <input type="number" name="yearsNum" id="number-years" min="1" max="50" required/>
        <input type="submit" value="Show costs"/>
    </p>
</form>
<table>
    <thead>
    <tr>
        <th>Year</th>
        <th>January</th>
        <th>February</th>
        <th>March</th>
        <th>April</th>
        <th>May</th>
        <th>June</th>
        <th>July</th>
        <th>August</th>
        <th>September</th>
        <th>October</th>
        <th>November</th>
        <th>December</th>
        <th>Total</th>
    </tr>
    </thead>
    <tbody>
    <?php
    if (!array_key_exists('yearsNum', $_POST) || intval($_POST['yearsNum']) <= 0) {
        die('The Form can\'t been Empty!!!');
    }

    $yearsNum = (int)$_POST['yearsNum'];
    $currentYear = (int)date("Y", time());
    for ($i = $currentYear - 1; $i >= ($currentYear - $yearsNum); $i--) {
        $total = 0;
        ?>
        <tr>
            <td><?= $i ?></td>
            <?php
            for ($j = 0; $j < 12; $j++) {
                $month_expenses = rand(0, 999);
                $total += $month_expenses;
                echo "<td>$month_expenses</td>";
            }
            ?>
            <td><?= $total ?></td>
        </tr>
    <?php
    }
    ?>
    </tbody>
</table>
</body>
</html>