(a)the amount determined as per the following formula shall be charged under section 67 as income of the tax year in which three years from the date of the transfer of the original asset expires:––X—Y,where,––X = the capital gains not charged under section 67 as per sub-section (1).Y = the capital gains that would not have been charged under section 67, if the cost of the new asset had been taken to be the amount actually utilised for purchase or construction of the new asset;