This week, the ratings of five Diversified Telecommunication Services stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Nippon Telegraph & Telephone (NYSE:NTT) falls to a D (“sell”), worse than last week’s grade of C (“hold”). Nippon Telegraph & Telephone provides a variety of telecommunication services, including telephone, telegraph, leased circuits, data communication, terminal equipment sales, and related services. To get an in-depth look at NTT, get Portfolio Grader’s complete analysis of NTT stock.

Level 3 Communications (NYSE:LVLT) gets weaker ratings this week as last week’s C drops to a D. Level 3 is an integrated communications network company that provides Internet Protocol and data services, content distribution services, colocation services, and softswitch and voice services. The stock also gets an F in Equity. For more information, get Portfolio Grader’s complete analysis of LVLT stock.

This is a rough week for Hickory Tech (NASDAQ:HTCO). The company’s rating falls to D from the previous week’s C. Hickory Tech is a diversified communications company that offers a full array of telecommunications products and services to business and residential customers. The stock also rates an F in Earnings Revisions. For a full analysis of HTCO stock, visit Portfolio Grader.

Windstream (NASDAQ:WIN) earns a F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). Windstream is a company that provides communications and technology solutions, including high-speed Internet access, digital television services, and voice services. The stock also gets an F in Margin Growth. As of Oct. 3, 2012, 11.1% of outstanding Windstream shares were held short. The stock’s trailing PE Ratio is 32.90. Over the last month, shares of the company are down 0.1%, worse than the Nasdaq’s 1.7% increase for the same time period. To get an in-depth look at WIN, get Portfolio Grader’s complete analysis of WIN stock.

Telecom Italia (NYSE:TI) is having a tough week. The company’s rating falls from a D to a F rating. Telecom Italia SPA is engaged in communications, particularly in fixed and mobile national and international telecommunications, television and office products. The stock also rates an F in Sales Growth. For more information, get Portfolio Grader’s complete analysis of TI 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.