This week, these five stocks have the worst ratings in Operating Margin, one of the eight Fundamental Categories on Portfolio Grader.

Sears Hometown & Outlet Stores, Inc.. The company also gets F’s in operating margin growth. For more information, get Portfolio Grader’s complete analysis of SHOS stock.

Gastar Exploration, Inc. (GST) is a natural gas exploration company. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings revisions, and earnings surprise. For more information, get Portfolio Grader’s complete analysis of GST stock.

Newfield Exploration Company (NFX) is an independent crude oil and natural gas exploration and production company. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings revisions, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of NFX stock.

Fuel Tech, Inc. (FTEK) develops and commercializes air pollution control technologies and provides engineering services. The company also gets F’s in operating margin growth. For more information, get Portfolio Grader’s complete analysis of FTEK stock.

Carrizo Oil & Gas, Inc. (CRZO) is engaged in the exploration, development, production and transportation of natural gas and oil, mainly in the United States. The company also gets F’s in sales growth, operating margin growth, earnings growth, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of CRZO stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.