S. 40(a)(ia) : Amounts not deductible-Deduction at source– Labour charges–Failure to deduct tax at source-As per amendment brought to Finance Act, 2014 in s. 40(a)(ia) w.e.f. 01.04 2015, disallowance is restricted to 30% of amount of expenditure claimed-Amendment is applicable to retrospective effect. [S. 194C, 194H]