The amount of the reserve account for losses on returned goods that was included in necessary expenses in calculating the amount of business income for tax year 2017 of an individual that carried on a covered business before the effective date (other than an individual covered by the transitional rule) pursuant to the provisions of Article 53, paragraph (1) of the former Income Tax Act, and any other amount specified by Cabinet Order as equivalent thereto, are included in gross revenue in calculating the amount of business income for tax year 2018.