Shares of C.H. Robinson Worldwide Inc. rallied 2.2% in midday trade Friday, enough to pace the Dow Jones Transportation Average's gainers, after the freight transportation company boosted its share repurchase program. The company said late Thursday that it was adding 15 million shares to its buyback program, which had 1.2 million shares remaining in the program that was authorized in 2013. With 139,237,319 shares outstanding as of May 10, the company can now reduce its shares outstanding by about 11.6%. The stock's price gain of $1.88 was adding about 11.5 points to the Dow transports' price, which was up 99 points, or 0.9%. Meanwhile, the Dow Jones Industrial Average was up 52 points, or 0.2%.