In Riverside County, the board of supervisors shall fix the salary of regular official reporters, which shall not be less than an annual salary of twenty thousand two hundred ten dollars ($20,210) and the compensation of official reporters pro tempore, which shall be at a rate not less than seventy-five dollars and twenty-five cents ($75.25) a day, for reporting in shorthand all proceedings in the superior court as required by law or the order of the superior court.