The overall ratings of three e-commerce stocks are down on Portfolio Grader this week. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, 1-800-FLOWERS.COM, Inc. Class A (FLWS) falls to a D (“sell”), worse than last week’s grade of C (“hold”). 1-800-Flowers.com provides customers around the world with the freshest flowers and finest selection of plants, gift baskets, gourmet foods and confections, and plush stuffed animals perfect for every occasion. The stock has a trailing PE Ratio of 36.50. For a full analysis of FLWS stock, visit Portfolio Grader.

The rating of PetMed Express, Inc. (PETS) slips from a C to a D. PetMed Express offers prescription and nonprecription pet medications, as well as health and nutritional supplements. As of June 2, 2014, 21.6% of outstanding PetMed Express, Inc. shares were held short. To get an in-depth look at PETS, get Portfolio Grader’s complete analysis of PETS stock.

Amazon.com, Inc. (AMZN) is having a tough week. The company’s rating falls from a C to a D. Amazon.com is an online retailer that offers a wide range of products. The stock gets F’s in Earnings Revisions and Earnings Surprise. The stock’s trailing PE Ratio is 490.10. For more information, get Portfolio Grader’s complete analysis of AMZN 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.