At top to create arrays and time function:
<?
$time = microtime();
$time = explode(' ', $time);
$time = $time[1] + $time[0];
$start = $time;
?>
At bottom to process and pass values:
<?
$time = microtime();
$time = explode(' ', $time);
$time = $time[1] + $time[0];
$finish = $time;
$total_time = round(($finish - $start), 4);
echo '<p>Page generated in '.$total_time.' seconds.</p>'."\n";
?>