Taxes will increase by $569.2 billion if health reform legislation is enacted -- the largest in history, according to Rep. Dave Camp (D-Mich.).
"That's the largest we've ever had," he told reporters.
Camp is ranking Republican on the tax-writing Ways and Means Committee.
The 3.8 percent tax on investments increases taxes by $210 billion over 10 years.
The U.S. Chamber of Commerce joined 14 other groups in a letter to congressional leaders condemning the tax, saying it "embraces the worst features of the financing provisions in the House- and Senate-passed bill."
A vote on this measure is expected Sunday when the House take up the entire reform package.