(2)In computing such income, an allowance shall be made in respect of the cost of planting rubber plants in replacement of plants that have died or become permanently useless in an area already planted, if such area has not previously been abandoned, and for the purpose of determining such cost, no deduction shall be made in respect of the amount of any subsidy which, under the provisions of clause (31) of section 10, is not includible in the total income.
