This week, four tech services stocks are improving their overall rating on Portfolio Grader. Each of these rates an “A” (“strong buy”) or “B” overall (“buy”).

Gartner, Inc. (IT) is bettering its rating of C (“hold”) from last week to a B (“buy”) this week. Gartner provides research and analysis on the computer hardware, software, communications, and related information technology industries. In Portfolio Grader’s specific subcategory of Equity, IT also gets an A. For more information, get Portfolio Grader’s complete analysis of IT stock.

Blackhawk Network Holdings Inc Class A (HAWK) is making headway this week, with the company’s rating improving to an A (“strong buy”) from a B (“buy”) last week. For more information, get Portfolio Grader’s complete analysis of HAWK stock.

Western Union Company (WU) shows solid improvement this week. The company’s rating rises from a C to a B. Western Union is engaged in global money transfer and payment services. Shares of the stock have been changing hands at an unusually rapid pace, twice the rate of the week prior. For more information, get Portfolio Grader’s complete analysis of WU stock.

Convergys Corporation (CVG) gets a higher grade this week, advancing from a C last week to a B. Convergys provides customer management business process outsourcing solutions for communications, financial services, technology, and other vertical markets in North America and internationally. Shares of the stock have been trading at an exceptionally rapid pace, up threefold from the week prior. For more information, get Portfolio Grader’s complete analysis of CVG 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.