• Ticker: CHRW
• YTD stock performance: -7%
• Fortune 500 rank: 237

Change can be a good thing -- except when it hits profit margins.

C.H. Robinson (CHRW), a shipping and logistics provider, diversified its business model in 2013 but struggled to sell investors on its growth strategy. Long a player in the third-party trucking business (it doesn't actually own the trucks, but organizes transportation on behalf of others), the company expanded into international freight forwarding when it purchased Phoenix International in late 2012.

But increased costs associated with Phoenix's integration have eaten into profits, and every time the company reported quarterly earnings in 2013, shares fell. The biggest drop came in May, when the stock plunged 7% on weaker-than-expected first quarter results.

But despite recent downgrades from several Wall Street analysts, management remains bullish.

"This is the biggest transformation initiative that we've ever undergone in my 20 years here," said chairman and CEO John P. Wiehoff about the Phoenix acquisition. "This is going to position us for the future." --J.S.

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