This week, the ratings of three e-commerce stocks on Portfolio Grader are down. 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’s trailing PE Ratio is 36.70. For more information, get Portfolio Grader’s complete analysis of FLWS stock.

This is a rough week for PetMed Express, Inc. (PETS). The company’s rating falls to D from the previous week’s C. PetMed Express offers prescription and nonprecription pet medications, as well as health and nutritional supplements. As of Nov. 24, 2014, 26.3% 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) gets weaker ratings this week as last week’s C drops 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. 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.