Held that from the assessment years of 2007-08 to 2011-12, the assessee had offered income from carbon credits amounting to Rs. 3,09,67,422 and the Department had accepted it as other income. Now the assessee wrote off this amount due to non-recognition of the project. The same treatment which was given by the Department to the income of the assessee on carbon credits during the last five years had to be given by the Department. Accordingly, the Assessing Officer was to re-examine this issue of disallowance on carbon credits. Held that the prior period expenditure could not be allowed in assessing the income of a particular year. The assessee did not make provision in respect of prior period expenses nor filed revised return.   (AY. 2012-13)