1. International Accounting Standards Board (IASB). (2003). International Accounting Standard 17 Leases.
Paragraph 33: "Lease payments under an operating lease shall be recognised as an expense on a straight-line basis over the lease term unless another systematic basis is more representative of the time pattern of the user’s benefit." This paragraph directly mandates the straight-line method used in the calculation.
2. Kieso
D. E.
Weygandt
J. J.
& Warfield
T. D. (2020). Intermediate Accounting
IFRS Edition (4th ed.). John Wiley & Sons.
Chapter 21
Leases
Section on Operating Lease - Lessee: This chapter explains that for operating leases with uneven payment patterns (such as a rent-free period)
the total lease payment is allocated evenly over the lease term. The difference between the recognized expense and the cash paid in a period is recorded as a lease liability (accrual) or lease asset (prepayment).
3. University of Cambridge
Judge Business School. (n.d.). MFin Accounting Course Materials - Module on Leases.
Section: Accounting for Operating Leases under IAS 17: Course notes illustrate that when lease payments are not made on a straight-line basis (e.g.
rent holidays)
the total cost is annualized. For a rent-free initial period
an expense is recognized along with a corresponding accrual
reflecting the consumption of the economic benefit of using the asset.