This week, three Diversified Telecommunication Services stocks are improving their overall rating on Portfolio Grader. Each of these rates an “A” (“strong buy”) or “B” overall (“buy”).

CenturyLink (NYSE:CTL) is progressing from last week’s rating of B (“buy”) as the company improves to an A (“strong buy”) this week. CenturyLink is an integrated communications company engaged mainly in providing communications services, Internet and broadband services. In Portfolio Grader’s specific subcategory of Earnings Momentum, CTL also gets an A. At present, the stock has a dividend yield of 2.9%. For more information, get Portfolio Grader’s complete analysis of CTL stock.

This week, tw telecom (NASDAQ:TWTC) pushes up from a B to an A rating. TW Telecom is a national provider of managed network services that specializes in Ethernet and data networking, Internet access, local and long distance voice, VPN, VoIP and network security services. For more information, get Portfolio Grader’s complete analysis of TWTC stock.

Nippon Telegraph & Telephone‘s (NYSE:NTT) grade is moving up to a B (“buy”) this week from last week’s C (“hold”). Nippon Telegraph & Telephone provides a variety of telecommunication services, including telephone, telegraph, leased circuits, data communication, terminal equipment sales, and related services. For more information, get Portfolio Grader’s complete analysis of NTT 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.