Hauser's Law

clipped from online.wsj.com The chart nearby, updating the evidence to 2007, confirms Hauser's Law. The federal tax "yield" (revenues divided by GDP) has remained close to 19.5%, even as the top tax bracket was brought down from 91% to the present 35%. This is what scientists call an "independence theorem," and it cuts the Gordian Knot of tax policy debate. The data show that the tax yield has been independent of marginal tax rates over this period, but tax revenue is directly proportional to GDP. So if we want to increase tax revenue, we need to increase GDP. What happens if we instead raise tax rates? Economists of all persuasions accept that a tax rate hike will reduce GDP, in which case Hauser's Law says it will also lower tax revenue. That's a highly inconvenient truth for redistributive tax policy, and it flies in the face of deeply felt beliefs about social justice. It would surely be unpopular today with those presidential candidates who plan to raise tax rates on the rich – if they knew about it.