The ratings of 3 Chemicals stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Sherwin-Williams Company (SHW) drops from a B to a D rating. Sherwin-Williams Company manufactures, distributes, and sells paint, coatings and related products to professional, industrial, commercial, and retail customers. For more information, get Portfolio Grader’s complete analysis of SHW stock.

Core Molding Technologies, Inc. (CMT) experiences a ratings drop this week, going from last week’s C to a D. Core Molding Technologies, Inc. engages in the manufacture and sale of sheet molding compound (SMC) products in the United States, Canada, and Mexico. The company also gets F’s in sales growth and earnings growth. For more information, get Portfolio Grader’s complete analysis of CMT stock.

Slipping from a D to a F rating, Senomyx, Inc. (SNMX) takes a hit this week. Senomyx, Inc. discovers new proprietary flavor and fragrance molecules for use in a wide range of consumer products. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of SNMX 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.