This week, the ratings of three diversified telecommunication services stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Premiere Global Services, Inc. (PGI) falls to a D (“sell”), worse than last week’s grade of C (“hold”). Premiere Global Services is a global provider of conferencing and collaboration services. In Portfolio Grader’s specific subcategory of Earnings Momentum, PGI also gets an F. The trailing PE Ratio for the stock is 30.40. To get an in-depth look at PGI, get Portfolio Grader’s complete analysis of PGI stock.

inContact, Inc. (SAAS) experiences a ratings drop this week, going from last week’s C to a D. inContact provides cloud-based contact center software services and network connectivity in the United States. The stock gets F’s in Earnings Revisions and Equity. The stock price has fallen 9.7% over the past month, worse than the 1.3% decrease the Nasdaq has seen over the same period of time. For a full analysis of SAAS stock, visit Portfolio Grader.

KT Corporation Sponsored ADR’s (KT) rating falls this week to an F (“strong sell”), down from last week’s D (“sell”). KT provides telecommunication services including local, long distance, and international calling, satellite communication, data transmission, and wireless telephone services in South Korea. In Earnings Growth, Earnings Momentum, Earnings Revisions and Margin Growth the stock gets F’s. Shares of the stock have been changing hands at an unusually rapid pace, up 525.3% from the week prior. For more information, get Portfolio Grader’s complete analysis of KT 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.