The Government Accountability Office reported in 2008 that of the largest 100 U.S. companies, 86 had subsidiaries abroad, and 83 of these had subsidiaries in tax havens. Bank of America had 115 subsidiaries in tax havens, including 59 in the Cayman Islands. Citigroup had 427 tax haven subsidiaries, including 91 in Luxembourg and 90 in the Cayman Islands. Goldman Sachs only had 29, 15 in the Cayman Islands.
http://www.gao.gov/new.items/d09157.pdf