function avgAndMedian($cfs)
{
  $cfs = array_filter($cfs);
  $count = count($cfs);
  $average = array_sum($cfs) / $count;

  $middle_index = floor($count / 2);
  sort($cfs, SORT_NUMERIC);
  $median = $cfs[$middle_index];
  if ($count % 2 == 0) {
	$median = ($median + $cfs[$middle_index - 1]) / 2;
  }

  return array($average, $median);
}