What happened

Beer titan Molson Coors (TAP 0.54%) trailed the market last year as shares fell 16% compared to a 19% increase in the S&P 500, according to data provided by S&P Global Market Intelligence.

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The slump follows a period of heady optimism for the stock in the wake of Molson's deal to acquire the full MillerCoors portfolio from AnheuserBusch InBev in 2016.

So what

Things haven't turned out quite as well as investors had hoped since that acquisition closed. While its broader portfolio helped push international beer sales higher in 2017, Molson Coors struggled with a weak U.S. market during the same time.

A glass of beer sits on a coffee table with a sports broadcast in the background.

Image source: Getty Images.

In early November, the company revealed a 5.5% sales drop in the U.S. that pulled overall revenue down 2%.  

Now what

The company is working to diversify away from the premium light beer segment that's shrinking right now as consumers gravitate toward premium, imported brands. Rival Constellation Brands, for example, enjoyed a 10% sales spike in its beer segment last year on healthy demand for Corona and Modelo in the U.S. market.

Similarly, Molson's premium brands are its fastest growing products. But, since they represent a relatively small portion of the portfolio, overall growth is likely to stay weak for the time being. On the bright side, investors will be looking for continued financial improvements, including lower costs, reduced debt, and increased cash flow, when the company posts its fiscal fourth quarter results on Feb. 14.