Perfect Seconds Timestamp Likelihood Generator

<head><title>Random Timestamp Generator</title></head>
<body>
<?php
$tstotal=0;
for ($i=0; $i<10000; $i++) {
    $int= mt_rand(1571965200,1575539477); //October 25th, 2019 "launch date" of Team Trees to December 5th, 2019 when script was created.
    $string = date("Y-m-d H:i:s",$int);
    echo $string;
    if(date("s",$int) == "00")
    {
        echo " <b>Exact time!</b>";
        $tstotal++;
    }
    echo "<br/>";
}
echo "<br/>";
echo "Displaying <b>10000</b> random timestamps. Total perfect second timestamps: <b>";
echo strval($tstotal);
echo "</b>";

?>
</body>