Staples Struggles and Other #Stocks2Watch

#Stocks2Watch: FOX Business rounds up the stocks you should watch before the opening bell rings on Wall Street. Tweet @adamsamson or e-mail adam.samson@foxbusiness.com and tell us what stocks you're watching -- your picks could appear online!

1. Staples (NASDAQ:SPLS)

Staples (NASDAQ:SPLS) revealed weaker-than-expected quarterly results, a disappointing current-quarter outlook and plans to shutter 225 stores. The shares are plummeting 13%.

2. Pandora (NYSE:P)

Pandora (NYSE:P) said its market share, listener hours and active listeners climbed on a year-to-year basis in February. The online radio site also said it will stop providing monthly metrics, but will continue providing them on quarterly basis. The shares are slumping 3%.

3. Yum! Brands (NYSE:YUM)

Yum! Brands was upgraded by analysts at Robert W. Baird to "outperform" from "neutral." Shares of the KFC and Taco Bell parent are up about 1%.

4. Costco (NASDAQ:COST)

Costco (NASDAQ:COST) logged a bigger-than-expected drop in fourth-quarter profits as holiday discounting took a toll. The shares are sliding more than 3%.

5. Shanghai Chaori Solar Energy Science & Technology Co.

Shanghai Chaori Solar Energy Science & Technology Co. isn't traded publicly, but it's worth keeping an eye on anyway. Media reports say the company will be the first-ever default in the Chinese bond market after the company failed to secure bailouts from the local government. Bloomberg News even cited Bank of America as saying this could represent China's "Bear Stearns moment."