(2) The comparisons referred to in subsection (1) shall be carried out using the proportional value method of comparison,
(a) in the case of a comparison under clause (1)(a), as if the female job classes in the proxy establishment were male job classes of the seeking employer; and
(b) in the case of a comparison under clause (1)(b), as if the key female job classes of the seeking employer were male job classes of the seeking
