private function _writeExterncount($cxals)
	{
		$record   = 0x0016;          // Record identifier
		$length   = 0x0002;          // Number of bytes to follow

		$header   = pack("vv", $record, $length);
		$data     = pack("v",  $cxals);
		$this->_append($header . $data);
	}