This week, 15 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 4,174 stocks and only these 15 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. Shares of the stock have fallen 44.6% since January 1. This is worse than the S&P 500, which has seen a 11.9% increase over the same period. As of Dec. 14, 2012, 18.2% of outstanding Bill Barrett shares were held short. For more information, get Portfolio Grader’s complete analysis of BBG stock.

Coeur d’Alene Mines (NYSE:CDE) engages in the ownership, operation, exploration, and development of silver and gold mining properties primarily located in the United States, Mexico, Bolivia, Argentina, and Australia. Since the first of the year, CDE has dropped 5.8%. The stock’s trailing PE Ratio is 99.7000000000000028421709430404007434844970703125. For more information, get Portfolio Grader’s complete analysis of CDE 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. Since the start of the year, ERF has declined 48.6%. 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. Shares of EROC have seen a 25.6% drop since January 1. 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 have slipped 11.3% since the first of the year. 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. Since January 1, KCG has slumped 72%. For more information, get Portfolio Grader’s complete analysis of KCG stock.

Momenta Pharmaceuticals (NASDAQ:MNTA) is a biotechnology company. The price of MNTA has slipped 38.5% since the start of the year. 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. The price of MT is down 13.7% since the first of the year. For more information, get Portfolio Grader’s complete analysis of MT stock.

Mechel (NYSE:MTL) is a Russian metals and mining company, uniting producers of steel, rolled products, hardware, coal, iron ore concentrate, and nickel. Since the first of the year, MTL has slid 25.9%. For more information, get Portfolio Grader’s complete analysis of MTL stock.

NuSTAR Energy (NYSE:NS) transports and stores crude oil and refined products. Shares of NS are trading 20.8% lower than at the start of the year. For more information, get Portfolio Grader’s complete analysis of NS stock.

PMC-Sierra (NASDAQ:PMCS) designs, develops, markets, and supports semiconductor networking solutions. The price of PMCS is 5.5% lower than at 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 57.1%. As of Dec. 14, 2012, 12.7% 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. Shares of TLM stock have fallen 13.3% since January 1. 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.

EXCO Resources (NYSE:XCO) is an oil and natural gas company involved in the exploration, exploitation, development and production of onshore North American oil and natural gas properties. Since January 1, XCO has tumbled 25.7%. As of Dec. 14, 2012, 10.9% of outstanding EXCO Resources shares were held short. For more information, get Portfolio Grader’s complete analysis of XCO 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.