Caterpillar and four other Dow stocks that should win if dollar falls

The U.S. dollar index fell to a three-year low Wednesday and looks set for more declines, after Treasury Secretary Steven Mnuchin said a weak dollar was good for U.S. trade.

The dollar index is now down 10 percent in the past year and broke below the key 90 level after Mnuchin’s remarks. According to Kensho, there are some big winners in the Dow when the dollar is falling.

CNBC’s analysis looked at when the Dollar index is down five percent or more in a three month period. That happened 29 times since January, 1993.

The stock that did best on average while the dollar fell was Caterpillar, up 8.1 percent. 3M was the second best performer, averaging a 5.3 percent gain and Visa came in third, with a 5.2 percent gain.

Next was Apple with a 4.9 percent average gain, followed by Chevron, up an average 3.3 percent

CNBC also studied which sectors do best during the same type of dollar decline and found the top sector was materials, up an average 3.9 percent, followed by energy, up 3.1 percent and industrials, up an average 1.9 percent.

A weaker dollar was not as positive for the S&P 500, which was up just an average 0.7 percent in the same periods.

Disclosure: NBC Universal, CNBC parent, is a minority holder of Kensho