This week, 14 stocks get F’s (“strong strong”) in Portfolio Grader‘s three main grading categories, Total Grade, Overall Fundamental Grade, and Quantitative Grade.

These are the worst of the worst in the entire Portfolio Grader database. This week, there are 4,250 stocks and only these 14 get failing marks in all categories to make the dreaded “Triple F” stocks list. Here they are:

Bill Barrett (NYSE:BBG) explores for and develops oil and natural gas in the Rocky Mountain region of the United States. Since January 1, BBG has slumped 43.1%. This is worse than the S&P 500, which has seen a 11% increase over the same period. As of Dec. 28, 2012, 18.2% of outstanding Bill Barrett shares were held short. For more information, get Portfolio Grader’s complete analysis of BBG stock.

Enerplus (NYSE:ERF) is an oil and gas exploration and production company that owns a large, diversified portfolio of income-generating crude oil and natural gas properties. Shares of ERF have seen a 49% drop since January 1. For more information, get Portfolio Grader’s complete analysis of ERF stock.

Eagle Rock Energy (NASDAQ:EROC) engages in gathering, compressing, treating, processing, transporting, marketing, and trading natural gas, as well as fractionating and transporting natural gas liquids. The price of EROC is down 25.6% since the first of the year. For more information, get Portfolio Grader’s complete analysis of EROC stock.

International Rectifier (NYSE:IRF) is engaged in the design, manufacture, and marketing of power management semiconductors. Shares of IRF stock have fallen 7.7% since January 1. For more information, get Portfolio Grader’s complete analysis of IRF stock.

Knight Capital Grou (NYSE:KCG) provides trade execution services across multiple asset classes. Shares of KCG are trading 70.3% lower than at the start of the year. For more information, get Portfolio Grader’s complete analysis of KCG stock.

Legacy Reserves (NASDAQ:LGCY) acquires and explores for oil and natural gas properties in the United States. The price of LGCY has slipped 16% since the start of the year. For more information, get Portfolio Grader’s complete analysis of LGCY stock.

Momenta Pharmaceuticals (NASDAQ:MNTA) is a biotechnology company. Since January 1, MNTA has slumped 33.3%. For more information, get Portfolio Grader’s complete analysis of MNTA stock.

ArcelorMittal SA (NY Reg Sh) (NYSE:MT) is a global steel producer that makes finished and semi-finished steel products. Since the first of the year, MT has dropped 6.6%. For more information, get Portfolio Grader’s complete analysis of MT stock.

Navistar (NYSE:NAV) manufactures and markets medium and heavy trucks, school buses, mid-range diesel engines, and service parts. The price of NAV is 46.2% lower than at the first of the year. As of Dec. 28, 2012, 15.7% of outstanding Navistar shares were held short. For more information, get Portfolio Grader’s complete analysis of NAV stock.

NuSTAR Energy (NYSE:NS) transports and stores crude oil and refined products. Since the first of the year, NS has slid 20.6%. For more information, get Portfolio Grader’s complete analysis of NS stock.

PMC-Sierra (NASDAQ:PMCS) designs, develops, markets, and supports semiconductor networking solutions. Shares of PMCS have slipped 3.6% since the first of the year. For more information, get Portfolio Grader’s complete analysis of PMCS stock.

Thompson Creek Metals (NYSE:TC) is an integrated North American primary producer of molybdenum. Since January 1, TC has tumbled 44.3%. As of Dec. 28, 2012, 12.5% of outstanding Thompson Creek Metals shares were held short. For more information, get Portfolio Grader’s complete analysis of TC stock.

Talisman Energy (NYSE:TLM) is a global diversified upstream oil and gas company. Since the start of the year, TLM has declined 12.5%. For more information, get Portfolio Grader’s complete analysis of TLM stock.

Walter Energy Inc. (NYSE:WLT) is a producer and exporter of metallurgical coal for the global steel industry. The price of WLT has slipped 43.6% since the start of the year. For more information, get Portfolio Grader’s complete analysis of WLT 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.