The tax base of a payroll tax is: a. consumer expenditures. b. interest income. c. labor income. d. both (b) and (c) A payroll tax taxes a workers wages at 14 percent until the worker earns $60,000 per year. All labor earnings in excess of $60,000 are not subject to tax. The tax rate structure of the payroll tax is therefore: a. proportional. b. progressive. c. regressive. d. flat-rate