This week, 13 Oil Gas & Consumable Fuels stocks are worse, according to the Portfolio Graderdatabase. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Royal Dutch Shell Plc Sponsored ADR Class A (RDS.A) declines this week from a C to a D. Royal Dutch Shell Plc Sponsored ADR Class A explores for, produces, and refines petroleum. The company also gets F’s in sales growth, operating margin growth, earnings growth, and earnings surprise. For more information, get Portfolio Grader’s complete analysis of RDS.A stock.

Genesis Energy, L.P.’s (GEL) rating weakens this week, dropping to a D versus last week’s C. Genesis Energy, L.P. is involved in the oil and gas industry in the Gulf Coast region of the United States. The company also gets F’s in sales growth and earnings momentum. For more information, get Portfolio Grader’s complete analysis of GEL stock.

Shell Midstream Partners LP (SHLX) slips from a C to a D this week. The company also gets F’s in earnings momentum. For more information, get Portfolio Grader’s complete analysis of SHLX stock.

This is a rough week for Imperial Oil Limited (IMO). The company’s rating falls to F from the previous week’s D. Imperial Oil Limited produces and refines natural gas and petroleum products and manufactures petrochemicals. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings surprise, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of IMO stock.

SM Energy Company (SM) experiences a ratings drop this week, going from last week’s C to a D. SM Energy Company is an independent energy company that explores, exploits, develops, acquires and produces natural gas and crude oil in the United States. The company also gets F’s in sales growth, operating margin growth, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of SM stock.

Suncor Energy Inc. (SU) earns a D this week, moving down from last week’s grade of C. Suncor Energy Inc. is an integrated energy company in Canada. The company also gets F’s in sales growth, operating margin growth, and earnings surprise. For more information, get Portfolio Grader’s complete analysis of SU stock.

This week, Martin Midstream Partners L.P.’s (MMLP) rating worsens to a D from the company’s C rating a week ago. Martin Midstream Partners L.P. provides marine transportation, terminalling, distribution and logistical services for producers and suppliers of hydrocarbon products, specialty chemicals and other liquids. The company also gets F’s in sales growth, earnings revisions, earnings surprise, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of MMLP stock.

This week, Statoil ASA Sponsored ADR (STO) drops from a C to a D rating. Statoil ASA Sponsored ADR is involved in the development, production, transportation and marketing of crude oil, natural gas and extract natural gas liquids. The company also gets F’s in sales growth, earnings growth, earnings revisions, and earnings surprise. For more information, get Portfolio Grader’s complete analysis of STO stock.

Slipping from a D to a F rating, Cameco Corporation (CCJ) takes a hit this week. Cameco Corporation produces uranium and supplies conversion services commercially. The company also gets F’s in sales growth, earnings surprise, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of CCJ stock.

Westmoreland Coal Company (WLB) is having a tough week. The company’s rating falls from a C to a D. Westmoreland Coal Company mines coal, which is used to produce electric power, and owns power-generating plants. The company also gets F’s in free cash flow. For more information, get Portfolio Grader’s complete analysis of WLB stock.

Emerge Energy Services LP (EMES) gets weaker ratings this week as last week’s C drops to a D. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings revisions, earnings surprise, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of EMES stock.

Slipping from a C to a D rating, TOP Ships Inc. (TOPS) takes a hit this week. TOP Ships Inc. offers marine shipping services. The company also gets F’s in operating margin growth, earnings growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of TOPS stock.

Zion Oil and Gas, Inc. (ZN) gets weaker ratings this week as last week’s C drops to a D. Zion Oil and Gas, Inc. operates as a development stage oil and gas exploration company in Israel. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of ZN 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.