, In computing net income for taxing purposes a taxpayer is permitted 1 “A reasonable allowance for the exhaustion, wear and tear of property used in the trade or business, including a reasonable allowance for obsolescence. * * * ” The petitioner claimed depreciation on its motor equipment for the calendar year 1932 in the sum of $55,412.82, $35,627.28 of which was disallowed by the Commissioner of Internal Revenue. The taxpayer appealed to the Board of Tax Appeals following deficiency notice by the Commissioner of Internal Revenue. The Board of Tax Appeals sustained the Commissioner and the taxpayer petitions this court to review that decision.

The Board of Tax Appeals found-the facts to be substantially as follows:

The petitioner pursued a policy of maintenance and repair, which prolonged the life of its equipment, charging as expense amounts expended for reconditioning. Petitioner generally capitalized complete reconditioning but there is no evidence that such additions were charged to its equipment accounts. A policy of replacement of operating parts, such as batteries, transmissions and motors was followed so that maximum length of service might be obtained from all units, and these replacements were charged to expense. Amounts received for discarded equipment were credited to income, and accumulated depreciation on retired equipment charged to depreciation reserve.

The Commissioner of Internal Revenue declined to accept petitioner’s estimate of the useful life of individual units of its equipment and in its place fixed a useful life of equipment, for depreciation purposes, for used units at five years from the date of acquisition, and of new units at seven and one-half years. The Board of Tax Appeals upheld this ruling ( 36 B.T.A. 328 ) and the taxpayer petitions this court to review that decision.

The petitioner contends that it was entitled to a deduction of the full amount claimed for wear and tear and obsolescence on property owned by it; that the Commissioner’s method of determining depreciation for the year 1932 was arbitrary.

“Depreciation allowances must be based on intelligent estimates and not mere guesses.” Paul & Mertens, Law of Federal Income Taxation, Vol. 2, p. 561, Sec. 20.18. There is no burden on the Commissioner to prove the correctness of his assessment for, once he has formally determined the amount or rate of depreciation and made an assessment based thereon, the law presumes his action right and the assessment prima facie valid. Rieck v. Heiner, etc., 3 Cir., 25 F.2d 453, 454 . The Commissioner’s determination must give way, however, if proof shows his computation erroneous. Geuder, Paeschke & Frey Co. v. Commissioner, 7 Cir., 41 F.2d 308, 310 ; Cumberland Glass Mfg. Co. v. U. S., Ct.Cl., 44 F.2d 455, 460 ; Washburn Wire Co. v. Commissioner 1 Cir., 67 F.2d, 658, 660 ; Rieck v. Heiner, etc., supra.

The petitioner placed an estimated useful life (for depreciation-purposes) upon each unit of its equipment, whether acquired new or second hand. Most of these *106 units, as found by the Board, exceeded that estimated useful life and were not retired but remained in service. The petitioner failed to prove that its estimates were correct and succeeded only in proving them erroneous, thus sustaining the prima fácie correctness of the Commissioner’s method of computing the depreciation. The Commissioner’s rate is not arbitrary but, on the contrary, is in complete accord with the actual facts and life of the petitioner’s equipment, as borne out by the evidence. For example, taking from petitioner’s brief a list of cars “junked” we check the exhibits in the record to learn the year model iof each, thus being advised of the actual life of each car listed. Striking an average, we are informed that each car junked had a life of ten plus years which, even though we reduce it to nine years to compensate for possible inaccuracies, is considerably. greater than the seven and one-half year useful-life assigned by the Commissioner to cars purchased new.

-There is no evidence in the record which would justify overruling the findings of the Board-and its decision is, therefore,

Affirmed.

Revenue Act of 1932, 47 Stat. 169 , 179, § 23(k), 26 U.S.C.A. § 23 (7).