John Cochrane runs down how well-meaning programs meant to help the poor create a Poverty Trap:

That data from the Secretary of Public Welfare of the Commonwealth of Pennsylvania, Gary Alenander. A separate paper by Larry Kotlikoff and David Rapson, “Does it Pay, at the Margin, to Work and Save? Measuring Effective Marginal Taxes on Americans’ Labor and Saving.” study of couples in Massachusetts comes up with this calculation:

Meanwhile, the CBO considers considerably fewer benefit programs and presents this data on marginal tax rates: