WASHINGTON—Experts differ on how many U.S. jobs have been sent offshore, or may be. The McKinsey Global Institute, a pro-business research center, estimated earlier this year that 11 percent of ...

Auto-parts maker Delphi Corp., for example, has offshored 11,700 U.S. jobs since 2004, while textile makers have offshored at least 17,000 jobs since then, the Labor Department said.