American Companies Are Exposed, Too

At least 35 U.S. companies, including memory-chip technology maker Rambus (RMBS), Coach (COH), and Tiffany (TIF), derive 15 percent or more of their revenues from Japan, according to data compiled by Bloomberg, and they risk losing business in the wake of the tragedy there. About 75 percent of Aflac's (AFL) 2010 sales come from Japan, the highest amount among U.S. companies with a market value of $100 million or more.

Some U.S.-owned plants in Japan got hit by the earthquake. Texas Instruments (TXN) said its silicon wafer plant in Miho, Japan, had sustained "substantial" damage. The plant accounts for 10 percent of company revenue. U.S.-based retailers will be vulnerable to shifts in consumer behavior as the nation rebuilds. "Even for Japanese consumers who have the means, they may not be in the mood to open up their wallets," says Lawrence Creatura, fund manager at Federated Investors in Rochester, N.Y. Coach shuttered 20 of its 165 stores in Japan in response to the quake and cut staff and shortened hours at others. Tiffany closed some of its 55 outlets. "The situation is fluid," says Tiffany spokesman Mark Aaron.