Section 39(1)(e) in The U.P. Zamindari Abolition and Land Reforms Act, 1950
(e)average annual income from forests, which shall be computed-(i)on the basis of the income for a period of twenty to forty agricultural years immediately preceding the dale of vesting as the Compensation Officer may consider reasonable; and(ii)on the appraisement of the annual yield of the forest on the date of vesting.