This week, the energy services, marine, construction and engineering, electrical equipment and metals and mining sectors look weak according to Portfolio Grader.

With 91% of its stocks (50 out of 55) rated “sell,” the energy services sector is struggling this week. CARBO Ceramics (CRR), Tidewater (TDW) and Transocean (RIG) are pushing the sector down with F grades.

The marine sector is lagging this week with 71% of its stocks (5 out of 7) rated a “sell”. Out of the marine stocks, Seaspan Corporation (SSW) and Kirby Corporation (KEX) are at the bottom with F’s. Diana Shipping (DSX) also has a weak D.

The construction and engineering sector looks weak, with 67% of its stocks (14 out of 21) rated a “sell”. With an overall grade of F, Empresas ICA SAB de CV Sponsored ADR (ICA), KBR, Inc. (KBR) and Jacobs Engineering Group (JEC) are weighing down the sector.

The electrical equipment sector is trailing behind others this week, with 62% of its stocks (16 out of 26) rated a “sell”. General Cable Corporation (BGC), Graftech International Ltd (GTI) and Encore Wire Corporation (WIRE) are dragging down the sector overall, each earning a low grade of F.

The metals and mining sector is dragging, with 56% of its stocks (48 out of 85) rated a “sell”. Among metals and mining stocks, Vale S.A. Sponsored ADR (VALE), Freeport-McMoRan, Inc. (FCX) and Companhia Siderurgica Nacional Sponsored ADR (SID) are lingering near the bottom with grades of F.

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.