Four depreciation methods,which are widely used at home and abroad,are discussed in detail. They are straightline depreciation (SL),sum of years digits depreciation,(SOYD),fixed rate depreciation (FRD) and double declining balance depreciation (DDB).

• 主要讨论目前国内外广泛应用的 4种折旧方法 ；即直线折旧法 (SL法 )、年数总和折旧法(SOYD法 )、双倍余额递减折旧法 (DDB法 )、定率递减折旧法 (FRD法 ) .