For the current week, the overall ratings of 16 Oil and Gas stocks are worse, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Peabody Energy (NYSE:BTU) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). Peabody Energy mines steal, coal, and metallurgical coal to sell to electric utilities and industrial customers. The stock price has fallen 22.5% over the past month, worse than the 0.7% increase the S&P 500 has seen over the same period of time. For a full analysis of BTU stock, visit Portfolio Grader.

This week, Consol Energy (NYSE:CNX) drops from a D to an F rating. Consol Energy is an energy producer and energy services provider that mainly serves the electric power generation industry in the United States. The stock also gets an F in Sales Growth. Shares of CNX dropped 10.8% since last month. To get an in-depth look at CNX, get Portfolio Grader’s complete analysis of CNX stock.

EQT Corp.‘s (NYSE:EQT) rating falls to a D (“sell”) this week, down from C (“hold”) the week prior. EQT offers energy products, primarily natural gas and NGLs, and services to wholesale and retail customers in the United States. The price of EQT went down 2.3% since last month. For more information, get Portfolio Grader’s complete analysis of EQT stock.

The rating of Cameco (NYSE:CCJ) slips from a C to a D. Cameco produces uranium and supplies conversion services commercially. The stock also rates an F in Earnings Surprise. Share prices fell 10.8% over the past month. For a full analysis of CCJ stock, visit Portfolio Grader.

This is a rough week for BP (NYSE:BP). The company’s rating falls to D from the previous week’s C. BP is involved in the supply, trading, refining, manufacturing, marketing and transportation of crude oil, petroleum, and chemical products to wholesale and retail customers. The stock also gets an F in Earnings Momentum. Shares of BP dropped 2.1% from a month ago. For more information, get Portfolio Grader’s complete analysis of BP stock.

The rating of Stone Energy (NYSE:SGY) declines this week from a C to a D. Stone Energy is an independent oil and natural gas company engaged in the acquisition, exploration, exploitation, development and operation of oil and gas properties. The stock also rates an F in Earnings Revisions. The price of SGY declined 12.9% from that of last month. To get an in-depth look at SGY, get Portfolio Grader’s complete analysis of SGY stock.

PDC Energy (NASDAQ:PETD) experiences a ratings drop this week, going from last week’s C to a D. PDC is an oil and gas company with drilling and production operations in the Rocky Mountains, the Appalachian Basin, and Michigan. The stock gets F’s in Earnings Revisions and Cash Flow. As of Aug. 3, 17% of outstanding PDC Energy shares were held short. Shares of PETD have declined 9.6% since last month. For a full analysis of PETD stock, visit Portfolio Grader.

Concho Resources (NYSE:CXO) earns a D this week, falling from last week’s grade of C. Concho Resources engages in the acquisition, exploration, and development of oil and natural gas properties in the United States. The stock also gets an F in Earnings Momentum. Since last month, CXO shares have dropped 2.8%. To get an in-depth look at CXO, get Portfolio Grader’s complete analysis of CXO stock.

EV Energy (NASDAQ:EVEP) is having a tough week. The company’s rating falls from a C to a D rating. EV Energy acquires, develops and produces oil and natural gas properties in the United States. The stock also gets an F in Cash Flow. For more information, get Portfolio Grader’s complete analysis of EVEP stock.

Slipping from a D to an F rating, Tsakos Energy Navigation (NYSE:TNP) takes a hit this week. Tsakos Energy Navigation provides international seaborne crude oil and petroleum product transportation services. The stock receives F’s in Earnings Growth, Earnings Momentum, and Equity. Cash Flow and Margin Growth also get F’s. The stock price has fallen 10.1% over the past month. To get an in-depth look at TNP, get Portfolio Grader’s complete analysis of TNP stock.

Royal Dutch Shell (NYSE:RDS.A) gets weaker ratings this week as last week’s C drops to a D. Royal Dutch Shell explores for, produces, and refines petroleum. The stock gets F’s in Earnings Growth and Earnings Surprise. Since last month, shares of RDS.A have stayed flat. For more information, get Portfolio Grader’s complete analysis of RDS.A stock.

This week, Whiting USA Trust‘s (NYSE:WHX) rating worsens to a D from the company’s C rating a week ago. Whiting USA is a trust of the Whiting Petroleum company that holds an interest for trust unitholders in oil and natural gas properties. The stock also gets an F in Earnings Surprise. Investors seem to agree with the downgrade and have pushed down the share price 46.9% over the past month. For a full analysis of WHX stock, visit Portfolio Grader.

Penn West Petroleum (NYSE:PWE) earns an F this week, moving down from last week’s grade of D. Penn West Energy Trust acquires, develops, exploits, and holds interests in petroleum and natural gas properties and assets. The stock gets F’s in Earnings Growth, Earnings Momentum, Earnings Revisions, and Cash Flow. PWE shares have fallen 2.6% from a month ago. To get an in-depth look at PWE, get Portfolio Grader’s complete analysis of PWE stock.

Triangle Petroleum‘s (AMEX:TPLM) rating weakens this week, dropping to a D versus last week’s C. Triangle Petroleum acquires, explores, and develops mineral properties. The stock gets F’s in Earnings Revisions, Equity, and Cash Flow. As of Aug. 3, 104.3% of outstanding Triangle Petroleum shares were held short. Since last month, the price of TPLM has declined 2.2%. For more information, get Portfolio Grader’s complete analysis of TPLM stock.

Slipping from a D to an F rating, Uranium Energy (AMEX:UEC) takes a hit this week. Uranium Energy is an exploration-stage company that explores and develops mineral properties in the United States and Paraguay. The stock gets F’s in Earnings Revisions, Equity, and Cash Flow. As of Aug. 3, 15.6% of outstanding Uranium Energy shares were held short. UEC shares dropped by 15.9% from the previous month. For a full analysis of UEC stock, visit Portfolio Grader.

Gastar Exploration (AMEX:GST) earns an F this week, falling from last week’s grade of D. Gastar Exploration is a natural gas exploration company. The stock gets F’s in Earnings Revisions, Equity, and Cash Flow. Shares of the company have fallen 10.3% since last month. For more information, get Portfolio Grader’s complete analysis of GST 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.