20. Carry forward of allowances

Where, in any year of assessment, full effect cannot, by reason of an insufficiency of gains or profits chargeable for that year of assessment, be given to any allowance falling to be made under the provisions of section 13, 14, 16, 17 or 19, then, so long as the person entitled thereto

Income Tax continues to carry on the trade, profession or business in respect of the gains or profits of which the allowance falls to be made, the balance of the allowance shall be added to, and be deemed to form part of, the corresponding allowance, if any, for the next succeeding year of assessment, and, if no such corresponding allowance falls to be made for that year, is deemed to constitute the corresponding allowance for that year, and so on for subsequent years of assessment.