Monetary threshold prescription replaces fixed limits in section seventeen, allowing amounts to be prescribed from the next fiscal year. Amendment to the Income-tax Act substitutes fixed monetary ceilings in section 17(2) with authority to prescribe amounts, replacing the fixed figure in sub-clause (iii)(c) and the fixed figure in the proviso after sub-clause (viii), clause (vi), clause (B) with 'such amount as may be prescribed,' effective from the start of the specified fiscal year.