23. In regulation 22 of the Disability Working Allowance Regulations (calculation of net earnings of employed earners) for sub-paragraph (b) of paragraph (4) there shall be substituted the following sub-paragraph—
“(b)where the weekly amount of those earnings equals or exceeds the lower earnings limit, an amount representing primary Class 1 contributions under the Contributions and Benefits Act, calculated by applying to those earnings the initial and main primary percentages applicable at the date of claim in accordance with section 8(1)(a) and (b) of that Act; and”.