The lease term is the non-cancellable period together with optional extension periods whose exercise is reasonably certain and optional termination periods whose non-exercise is reasonably certain, judged on every fact creating an economic incentive: contractual terms for optional periods against market rates, significant leasehold improvements, termination costs and relocation costs, the importance of the asset to operations, and conditions attached to exercise. The shorter the non-cancellable period, the more likely an extension; past practice on similar assets informs the judgement. A lease is no longer enforceable once both parties can terminate without more than an insignificant penalty, and an option exercisable only with the lessor's agreement is not an option. The lessee reassesses reasonable certainty on a significant event or change in circumstances within its control that affects the earlier conclusion (such as significant improvements, a significant modification or customisation, a business decision such as a relocation, or subleasing beyond the term), and the term is revised when the non-cancellable period itself changes through exercise, non-exercise or contractual compulsion. Lessors do not reassess the term after inception.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.