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

Northern Trust Corporation (NTRS) is a financial holding company that provides investment management, asset and fund administration, fiduciary, and banking solutions for corporations, institutions, and affluent individuals. The company also gets F’s in earnings revisions. For more information, get Portfolio Grader’s complete analysis of NTRS stock.

Brooks Automation, Inc. (BRKS) provides automation, vacuum, and instrumentation solutions to original equipment manufacturers and users throughout the world. The company also gets F’s in operating margin growth and earnings revisions. For more information, get Portfolio Grader’s complete analysis of BRKS stock.

Century Aluminum Company (CENX) produces primary aluminum, which is an internationally traded commodity. The company also gets F’s in sales growth, operating margin growth, and earnings revisions. For more information, get Portfolio Grader’s complete analysis of CENX stock.

GP Strategies Corporation (GPX) provides performance improvement services and products. The company also gets F’s in earnings revisions. For more information, get Portfolio Grader’s complete analysis of GPX stock.

Forward Air Corporation (FWRD) provides transportation services to air freight forwarders, air cargo carriers, and domestic and international airlines. The company also gets F’s in earnings revisions and earnings momentum. For more information, get Portfolio Grader’s complete analysis of FWRD 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.