The measure of wearing out , consumption or other reduction in the useful life of a fixed asset whether arising from use , effluxion of time or obsolescence through technology and market changes is called depreciation 对固定资产在使用期限内磨损、消耗和其他原因减少的一种估量称为折旧，这些价值的减少是由于使用中的磨损、时间的推移或技术的进步及市价的变动引起的价值损失。
