This week, the overall grades of three Insurance stocks are lower, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

StanCorp Financial Group (NYSE:SFG) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. StanCorp Financial Group is a holding company that conducts business through wholly-owned operating subsidiaries throughout the United States. In Portfolio Grader’s specific subcategory of Earnings Revisions, SFG also gets an F. For more information, get Portfolio Grader’s complete analysis of SFG stock.

Prudential Financial (NYSE:PRU) experiences a ratings drop this week, going from last week’s C to a D. Prudential Financial provides financial services throughout the United States and several locations worldwide. The stock also gets an F in Earnings Surprise. For a full analysis of PRU stock, visit Portfolio Grader.

The rating of OneBeacon Insurance Group (NYSE:OB) slips from a C to a D. OneBeacon Insurance Group offers specialized insurance products and services. The stock also rates an F in Earnings Surprise. To get an in-depth look at OB, get Portfolio Grader’s complete analysis of OB 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.