Image: Greenbrier Companies.

The stock market finished the week on a quiet note, and investors finished the day with major market benchmarks very close to the unchanged level. Initial reports that the Consumer Price Index rose an unexpected 0.3% in January fueled an early slide on Wall Street, but investors quickly helped the market rebound from the bulk of its losses, and the Nasdaq Composite actually finished the day with a solid gain. Still, some stocks weren't able to recover, and Valeant Pharmaceuticals (BHC 0.77%), Greenbrier Companies (GBX 0.94%), and Icahn Enterprises (IEP -1.38%) all finished the day with substantial losses.

Valeant Pharmaceuticals dropped almost 10% after another analyst released a negative report on the drugmaker. The report pointed to the damage to Valeant's reputation that its board and executive team have wrought, and it believes that Valeant still hasn't satisfactorily answered concerns about how the company accounts for some of its business, and the overall vision for the company's future.

Pointing to several somewhat unconventional accounting practices that Valeant has adopted, the analyst set a price target for the stock that was about a third below where it started the day. Despite the stock's plunge during the past year, Valeant still has a fairly optimistic following among investment analysts, making the report today stand out from the crowd.

Greenbrier fell 10% after railcar peer Trinity Industries (TRN 0.62%) released its fourth-quarter financial report Thursday night. Trinity shares dropped 22%, and investors pointed to the company's downbeat forecast for earnings as troublesome, not just for the company itself, but for the entire railcar industry. Trinity will do its best to cut costs and find business efficiencies, but it still expects earnings for 2016 to come between 30% and 45% below the consensus forecast among investors.

Greenbrier arguably faces similar conditions, and in its January quarterly report, Greenbrier said that backlog levels plunged, and new orders were disappointingly low. Both Greenbrier and Trinity trade at ridiculously low earnings multiples even based on forward earnings, suggesting that further hits to the bottom line could be yet to come.

Finally, Icahn Enterprises lost 11%. The investment partnership got bad news from credit rating agency Standard & Poor's, which said that it was considering cutting the bond rating on Icahn Enterprises' debt to below investment-grade level. With its current BBB- rating now on negative CreditWatch, Icahn Enterprises has nowhere to go but to junk-bond status, and that could result in much larger interest payments in the future.

The problem that S&P cited is the big drop in the value of Icahn Enterprises' investments, which included several hard-hit players in the energy and natural resources industries. Barring a quick bounce in the portfolio's value, Icahn Enterprises could face further declines if S&P makes good on its threat in the months to come.