public static function time_zone_options()
  {
    $options = array(
      'Pacific/Honolulu'    => '(GMT-10:00) Hawaii Time',
      'America/Juneau'      => '(GMT-09:00) Alaska Time',
      'America/Los_Angeles' => '(GMT-08:00) Pacific Time',
      'America/Denver'      => '(GMT-07:00) Mountain Time',
      'America/Phoenix'     => '(GMT-07:00) Mountain Time - Arizona',
      'America/Chicago'     => '(GMT-06:00) Central Time',
      'America/New_York'    => '(GMT-05:00) Eastern Time',
      'GMT'                 => '(GMT-00:00) Greenwich Mean Time'
    );
    return $options;
  }
}