Nov. 10 (Bloomberg) -- Shares of U.S. companies getting a majority of their sales overseas are doing the best this year on speculation the dollar’s decline to an almost 15-month low is boosting earnings.

The CHART OF THE DAY shows that shares of Standard & Poor’s 500 Index companies generating more than half of their revenue abroad have beaten those doing business only in the U.S. by 27 percentage points, according to data compiled by Bespoke Investment Group LLC, a Harrison, New York-based research firm. The falling dollar makes American goods more competitive overseas and boosts revenue when foreign currencies are brought back to the U.S.

“Lately, I’ve been really focusing on the multinationals,” said Stefanie Yeager, a fund manager at State College, Pennsylvania-based Vantage Investment Advisors LLC, which oversees $450 million. “The U.S. is just slowly coming out of the recession, so companies that are purely domestic still have their problems. The multinationals are really benefiting from the exchange rate.”

S&P 500 companies getting more than 50 percent of revenue from outside the U.S. have rallied 48 percent this year, according to Bespoke. At the same time, those with only U.S.- based sales rose 21 percent. The Dollar Index, a six-currency gauge of the greenback’s strength, is down 7.7 percent in 2009.

American equities and the U.S. currency are moving in the opposite direction more than ever before. The so-called correlation coefficient using 120 days of data between the Dollar Index and the S&P 500 is minus 0.44, near the level of minus 0.45 reached on July 7. The reading four months ago was the lowest in the currency gauge’s 42-year history.

To contact the reporter on this story: Lynn Thomasson in New York at lthomasson@bloomberg.net.

Last Updated: November 10, 2009 00:01 EST