The ratings of 4 Commercial Services & Supplies stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Clean Harbors, Inc. (CLH) is having a tough week. The company’s rating falls from a C to a D. Clean Harbors, Inc. provides environmental services and solutions to customers across North America. The company also gets F’s in earnings revisions. For more information, get Portfolio Grader’s complete analysis of CLH stock.

This week, HNI Corporation (HNI) drops from a C to a D rating. HNI Corporation manufactures and markets office furniture as well as hearth products. For more information, get Portfolio Grader’s complete analysis of HNI stock.

Cypress Energy Partners LP (CELP) earns a D this week, moving down from last week’s grade of C. The company also gets F’s in sales growth, earnings growth, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of CELP stock.

CECO Environmental Corp. (CECE) gets weaker ratings this week as last week’s D drops to a F. CECO Environmental Corp. provides air-pollution control technology products and services worldwide. The company also gets F’s in operating margin growth and earnings growth. For more information, get Portfolio Grader’s complete analysis of CECE 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.