(1)For the purposes of section 47, the annual rent in relation to a lease is—
(a)where the lease is not a partially continuing lease and the rent payable immediately before the appointed day was a cumulo rent, the annual rent allocated to the lease under section 40,
(b)where the lease is a partially continuing lease, the annual rent allocated to the converted subjects under section 41,
(c)in any other case, the annual rent payable under the lease.
(2)Any rent payable under the lease which is expressed wholly or partly in non-monetary terms is, to the extent that it is so expressed, to be left out of account.
(3)Any rent payable under the lease which is variable from year to year is, to the extent that it is so variable, to be left out of account.