The term reserve is common under IFRS. The use of "reserve" is discouraged using U.S. GAAP. Also, many long-term assets can be revaluated to fair value under IFRS, with the increase or decrease going through stockholder equity. For U.S. GAAP purposes, property, plant, and equipment accounts are recorded at historical cost, and when required, written down for impairment. No subsequent write-up to cost is available under U.S. GAAP, but IFRS allows the write-up of impaired assets. This is a major issue with U.S. GAAP users, where historical cost is one of the bedrock concepts of accounting theory.