This week, five tech services stocks are improving their overall ratings on Portfolio Grader. Each of these stocks is rated 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.

This week, Blackhawk Network Holdings, Inc. Class A (HAWK) is showing good progress as the company’s rating jumps from a B (“buy”) last week to an A (“strong buy”). 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 HAWK stock.

Western Union Company’s (WU) ratings are looking better this week, moving up to a B from last week’s C. Western Union is engaged in global money transfer and payment services. Shares of the stock have been trading at an exceptionally rapid pace, up twofold from 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. For more information, get Portfolio Grader’s complete analysis of CVG stock.

This week, Sabre Corp.’s (SABR) ratings are up from a B last week to an A. For more information, get Portfolio Grader’s complete analysis of SABR 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.