We’ve lived with supply side and trickle down economic theories for long enough that they can now be tested against reality. The theory was the lowering tax rates on the rich would encourage investment and growth which would be enjoyed by the non-rich as well. The reality is that it hasn’t worked. Lower tax rates on the rich show no correlation with employment growth, investment growth, productivity growth, GDP growth, real median income growth, or per capita revenue growth. Lower tax rates do not encourage growth. Retreating from the erroneous assumptions of the last three decades will not happen easily because so many practices have become new norms. At least the debate should be over.
(Click on the chart for the link.)

“A Graphical Assault On Supply-Side Tax Cuts” – Washington Post