submitting checkbox to php mail

I just need to submit 'Yes' if a checkbox has been clicked or 'NO' if it hasn't. Everything else is working and I can receive the email, but I do not get the value of the checkbox 'newsletter'.

html:

<label>
                  <label class="checkbox-inline">
                    <input type="checkbox" name="newsletter" id="newsletter" value="Yes" checked><label for="newsletter"><strong>I want to sign up for the newsletter.</strong></label>
                    </label>
                  </label>

php: `if(isset($_POST['email'])) {

$name = $_POST['name'];
$email = $_POST['email'];
$distributor = $_POST['distributor'];
$company = $_POST['company'];
$department = $_POST['department']; 
$country = $_POST['country'];
$comments = $_POST['comments']; 
$newsletter = $_POST['newsletter'];
    if ($newsletter != 'Yes') {
     $newsletter = 'No';
    }

$fields = array(
    0 => array(
        'text' => '<b>Name',
        'val' => $_POST['name']
    ),
    1 => array(
        'text' => '<b>Email',
        'val' => $_POST['email']
    ),
    2 => array(
        'text' => '<b>Distributor / Reseller',
        'val' => $_POST['distributor']
    ),
    3 => array(
        'text' => '<b>Company / Facility',
        'val' => $_POST['company']
    ),
    4 => array(
        'text' => '<b>Department',
        'val' => $_POST['department']
    ),
    5 => array(
        'text' => '<b>Country',
        'val' => $_POST['country']
    ),
    6 => array(
        'text' => '<b>Comments',
        'val' => $_POST['comments']
    ),
    7 => array(
        'text' => '<b>Join the mailing list?',
        'val' => $_POST['newsletter'],
    )
);

$message = "";

foreach($fields as $field) {
    $message .=  $field['text'].":</b> " . htmlspecialchars($field['val'], ENT_QUOTES) . "<br>\n";
}`