First Solar Inc.’s (FSLR) shares have plunged 21.2% in the past three months, underperforming the Zacks solar industry’s decline of 6.3% as well as the S&P 500’s return of 5.2%. However, it has outpaced the broader Zacks Oil-Energy sector’s loss of 31.7% in the same time frame. Image Source: Zacks Investment ResearchOther heavyweight solar stocks like Canadian Solar (CSIQ) , Enphase Energy (ENPH) and SolarEdge Technologies (SEDG) also performed poorly at the bourses, as evident from their share price loss o ...