President Obama has said he wants to raise marginal tax rates on high-income taxpayers. Yet under his policies, the largest increases in marginal tax rates may well apply not to the rich but to millions of middle-class families. These increases would not show up explicitly in the tax code but, rather, implicitly as part of health care reform. ...
A family of four with an income, say, of $54,000 would pay $9,900 for health care. That covers only about half the actual cost. Uncle Sam would pick up the rest.
Now suppose that the same family earns an additional $12,000 by, for example, having the primary earner work overtime or sending a secondary worker into the labor force. In that case, the federal subsidy shrinks, so the family’s cost of health care rises to $12,700.
In other words, $2,800 of the $12,000 of extra income, or 23 percent, would be effectively taxed away by the government’s new health care system.
That implicit marginal tax rate of 23 percent is a significant disincentive. And it comes on top of the explicit marginal tax rate the family already faces from income and payroll taxes. Altogether, many families would face marginal rates at or above the 50 percent level that animated the Reagan supply-side revolution. ...
None of this necessarily means that health reform is not worth doing. ... But we should not forget the cost of translating that noble aspiration into practical policy. ... Future generations of Americans may find health insurance more affordable, but they will also find hard work less financially rewarding.
--Greg Mankiw, NYT, on how subsidies that phase out with income are implicit marginal tax rate hikes