(a) The percentage of the undivided interest of each apartment owner in the common areas and facilities as expressed in the declaration may not be altered except in accordance with procedures set out in the bylaws and by amending the declaration.
(b) The bylaws must provide for a periodic reappraisal of the apartments and the common areas and facilities together with a recomputation, if required, of the percentage of the undivided interest of each apartment owner in the common areas and facilities.