CLEVELAND (Dec. 18)—PolyOne Corp.´s stock dropped by 50 percent to $3.20 a share on Dec. 18, pulling the maker of rubber and plastics materials stock to a 30-year low. Nearly 7.2 million PolyOne shares were traded Dec. 18, more than 12 times the number of shares posted the prior day. The plummeting stock price came a day after PolyOne announced that its fourth-quarter earnings outlook was worse than expected. The compounder said in its fourth-quarter projection that it anticipates a quarterly loss before special items of between $16 million and $20 million, or 17 cents to 22 cents a share. It also said sales for the fourth quarter will be lower than forecast, declining 12 percent from third-quarter volumes and equal to last year´s fourth quarter.