For the current week, the overall ratings of four insurance stocks are worse, according to the Portfolio Graderdatabase. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

XL Group Plc’s (XL) rating falls to a D (“sell”) this week, down from C (“hold”) the week prior. XL provides property, casualty and specialty products to industrial, commercial and professional firms worldwide. For Portfolio Grader’s specific subcategory of Earnings Momentum, XL also gets an F. For a full analysis of XL stock, visit Portfolio Grader.

National Interstate Corporation (NATL) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). National Interstate is a specialty property and casualty insurance company with a focus on the transportation industry. The stock also rates an F in Margin Growth. The stock’s trailing PE Ratio is 27.10. To get an in-depth look at NATL, get Portfolio Grader’s complete analysis of NATL stock.

This week, OneBeacon Insurance Group, Ltd. Class A’s (OB) rating worsens to a D from the company’s C rating a week ago. OneBeacon Insurance Group offers specialized insurance products and services. The stock also gets an F in Sales Growth. For a full analysis of OB stock, visit Portfolio Grader.

Enstar Group Limited (ESGR) earns a D this week, moving down from last week’s grade of C. Enstar acquires and manages insurance and reinsurance companies in run-off. The stock also gets an F in Margin Growth. For more information, get Portfolio Grader’s complete analysis of ESGR 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.