Unforeseen obsolescence is the loss in value on an asset due to a fall in demand for that type of asset that could not have been foreseen when the asset was acquired.

Unforeseen obsolescence may occur because of a new invention or discovery which destroys the market for the asset or because a shift in relative prices makes it uneconomical to continue using the asset.

It is not included in consumption of fixed capital but in “other changes in non-financial asset n.e.c.” in the “Other changes in assets account”. Unforeseen obsolescence is a synonym for " abnormal obsolescence".