The overall ratings of three tech services stocks are down on Portfolio Grader this week. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

ServiceSource International, Inc. (SREV) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). ServiceSource International helps hardware, software, healthcare, and life sciences companies derive from their customers more revenue from maintenance, support and subscription agreements. In Portfolio Grader’s specific subcategories of Earnings Momentum, Equity and Cash Flow, SREV also gets an F. To get an in-depth look at SREV, get Portfolio Grader’s complete analysis of SREV stock.

This week, China Information Technology, Inc. (CNIT) falls to a D (“sell”), worse than last week’s grade of C (“hold”). China Information Technology provides integrated solutions for the digital security sector, the Geographic Information Systems, or GIS sector, and the digital hospital information sector. The stock gets F’s in Equity, Cash Flow and Sales Growth. For more information, get Portfolio Grader’s complete analysis of CNIT stock.

Unisys Corporation’s (UIS) rating weakens this week, dropping to an F versus last week’s D. Unisys is an information technology company that provides outsourcing services, systems integration, consulting services and infrastructure services for its customers. The stock gets F’s in Earnings Revisions and Earnings Surprise. The trailing PE Ratio for the stock is 81.70. To get an in-depth look at UIS, get Portfolio Grader’s complete analysis of UIS 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.