For the purposes of this Part, the “normal rent” in respect of a lease for a period of account of the lessor (“L”) is the amount specified in subsection (2).

That amount is the amount that L would, apart from this Part, bring into account as rent from the lease that arises to L in that period of account for the purpose of determining L's liability to income tax for the related tax year or years.

For the meaning of “related tax year”, see section 614DB(4).