How much does ‘taxing the rich’ harm the economy? Harvard economist Greg Mankiw quotes this study:

A tax hike of 12.8 percentage points (one standard deviation) leads to 122 fewer hours of market work per adult per year and a 4.9 percentage point drop in the employment-to-population ratio. It also increases the size of the shadow economy by 3.8 percent of official GDP, and it reduces by 10 to 30 percent the share of national output and employment in “Retail Trade and Repairs,” in “Eating, Drinking, and Lodging,” and in a broader category that includes “Wholesale Trade and Motor Trade and Repair.” The evidence suggests that tax rate differences among rich countries are a major reason for large international differences in market work time and in the industry mix of market activity.

Greg Mankiw’s blog can be found here.