US GAAP generally does not require the component approach for depreciation.

While it would generally be expected that the appropriateness of significant assumptions within the financial statements would be reassessed each reporting period, there is no explicit requirement for an annual review of residual values.

In accordance with ASC 350-30-35-9, an entity should evaluate the remaining useful life of an intangible asset each reporting period to determine whether events or circumstances may indicate that a revision to the useful life (presumably shorter) is warranted to reflect the remaining expected use of the asset. Unlike the guidance that exists for long-lived intangible assets, there is no explicit requirement to evaluate the useful lives of long-lived tangible assets each reporting period. However, we believe the useful lives of long-lived tangible assets should be reassessed whenever events or circumstances indicate that a revision to the useful life (presumably shorter) is warranted.

IFRS requires that separate significant components of property, plant, and equipment with different economic lives be recorded and depreciated separately.

IAS 16, Property, plant and equipment, requires entities to review the residual value, useful life, and depreciation method applied to an asset, at a minimum at each balance sheet date.