<prompt> Translate the following text to EnglishKwa kifupi, muundo wa kiwango unaweza kuanzishwa ili kuwa ushindani au kuanzisha bei juu ya gharama halisi za barua, na shughuli za kushiriki kazi zinaweza kutokea kama matokeo ya asili.  <response>: In short, the rate structure could be established in order to be competitive or to base the prices on the actual costs of the mail, and worksharing activity could occur as a natural result. 