To clarify, CrCo or CrMe rituals which boost stats are momentary in casting, but permanent in long term effects, but those effects are not magically maintained, just like any ritual that builds something in a moment (Conjuring the Mystic Tower, for example). There would be one warping point for the ritual, but there wouldn't be any ongoing mystical effects, so nothing added on a yearly basis.
Gift or Reason, page 148 of the core book. Also, CrMe and CrCo guidelines list out the guidelines for increasing stat rituals.
 Technically the Tower should have 1 warping point, if you're tracking warping on objects.