It's a good thing forthat it's now making American cars. Worldwide exports from Japan fell for the seventh straight month in August to 286,000 units. That's down from 405,000 units in July, says the Japan Automobile Manufacturers Assn. During that month, Japan's exports of cars, trucks and buses to the U.S. dropped 45.6%, the largest drop in post-war history. Trade experts say increasing Japanese automaker production overseas, the weak U.S. dollar and the declining sports car market contribute to this phenomenon.