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

This week, WEX Inc. (NYSE:WEX) falls to a D (“sell”), worse than last week’s grade of C (“hold”). Winland Electronics designs and manufactures custom electronic controls and assemblies mainly for original equipment manufacturer customers, providing services from early concept studies through complete product realization. The stock currently has a trailing PE Ratio of 34.50. For a full analysis of WEX stock, visit Portfolio Grader.

VeriFone Systems, Inc. (NYSE:PAY) ratings are on the decline this week as the company earns an F (“strong sell”). Last week, it received a D (“sell”). VeriFone is engaged in the design, marketing, and service of transaction automation systems that enable secure electronic payments among consumers, merchants, and financial institutions. The stock receives F’s in Earnings Growth, Earnings Momentum, Earnings Revisions, and Margin Growth. For more information, get Portfolio Grader’s complete analysis of PAY stock.

Slipping from a C to a D rating, Teradata Corporation (NYSE:TDC) takes a hit this week. Teradata provides customers with enterprise data warehousing, including enterprise analytic technologies and services through software, hardware, and related business consulting and support services. The stock price has fallen 18% over the past month, worse than the 1.7% decrease the S&P 500 has seen over the same period of time. The stock has a trailing PE Ratio of 27.40. To get an in-depth look at TDC, get Portfolio Grader’s complete analysis of TDC 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.