The shorts must be getting fat on McDonald's (MCD) stock. 

Shares of the Golden Arches are down 8.8% year to date, lagging the Dow Jones Industrial Average's 5.2% gain. On Monday, the stock dropped below the 50-day moving average amid concerns from investment bank Stifel that McDonald's store remodels will continue to weigh on U.S. sales through early 2019. 

The stock slipped $2.70 to $158.14 in trading on Monday, below the 50-day moving average of $159.64. 

McDonald's investors haven't had many bullish items to chew on this year, so Stifel's note isn't anything new in and of itself. The stock has likely been plagued by rising labor and transportation costs, mixed second quarter sales in the U.S. and heavy discounting in the fast food industry. Chicken prices have also shot up since February, while beef prices have ticked slightly higher this year.   

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