For decades, most large employers bought group health insurance from insurers who charged them premiums on a per-worker basis. In 1993, a proposal for a national health insurance plan contained a provision requiring group health insurers to charge premiums based on payroll (in effect, financing health insurance by a payroll “tax”). Assuming the total premiums paid by employers remain the same, what are the labor market implications of this proposed change in the way in which health insurance is financed?