THE ACCOUNTING SYSTEM I: accounts of this classification at the time that the property is retired from service. The amount of this credit shall be charged concurrently as follows: “ An amount equal to the credit balance in the accrued depre- ciation balance-sheet account with respect to the property thus retired shall be charged to that account and the remainder (less salvage and insurance recovered, if any), together with the cost of demolishing the property, if demolished by or for the carrier, shall be charged to the accounts in Operating Expenses appropriate for the cost of repairs of the property before retire- ment. The accounting for the salvage shall be in accordance with the disposition made of the material recovered. “ If, however, the property retired and replaced with property of like purpose is of minor importance , such as a small roadway building or other small structure, and is replaced in kind with- out betterment, the cost of the replacement shall be charged to operating expense accounts, and no adjustment made in the road and equipment accounts. “If so authorized by the Interstate Commerce Commission, the carrier may charge to Profit and Loss any extraordinarily large item representing the cost of property retired and replaced, instead of charging such item to Operating Expenses. The carrier shall file with the Commission a statement of the cost and a description of the property retired and the reasons which, in its judgment, indicate the propriety of charging the cost of such property to Profit and Loss. “The provisions of this section are applicable in accounting (at the time of retirement) for the cost of property abandoned, even though the new property has been actually installed pre- viously to the date of the demolishment of the abandoned prop- erty. “ When the renewals to be made to an important building or other structure will constitute the major portion of its value when renewed, the property, when taken out of service, shall be considered as retired and accounted for as provided above, and for the purposes of this classification the renewed property shall be considered as an addition, and the appraised cost thereof shall be included in the accounts of this classification, considera- tion being given to the second-hand portions remaining therein. In no case shall the charge for the renewed property exceed the cost (at current market prices of labor and material) of new property of equal capacity and equal expectation of life in serv- 23]