64.1%

John Lott links to the Wall Street Journal's explanation of Obama's tax hikes on investments. Unsurprisingly, they do it better than I've been able to:

Keep in mind that dividends are paid to shareholders only after the corporation pays taxes on its profits. So assuming a maximum 35% corporate tax rate and a 44.8% dividend tax, the total tax on corporate earnings passed through as dividends would be 64.1%. . . .