The Los Angeles Business Journal’s index of largest local public companies rose 34 percent over the past year, in line with gains in the wider markets.

The weighted LABJ Stock Index closed at 187.37 on Dec. 31, the last trading day of 2013. Gainers for the year outpaced decliners 142 to 40. During the year 22 companies exited the index after being acquired or taken private, and 11 public companies were added to the index.

Most of biggest movers were biotech companies that have yet to put a product on the market. The biggest gainer was West L.A. cancer drug developer Puma Biotechnology Inc., soaring 452 percent to $103.53, followed by Pasadena drug developer Arrowhead Research Corp., which jumped 407 percent to $10.85. West L.A. cancer drug developer CytRx Corp. gained 235 percent $6.37.

Other big gainers benefited from management turnarounds and improved market outlooks after a poor showing in 2012. Entravision Communications Corp., a Santa Monica operator of Spanish-language TV and radio stations, rose 267 percent to $6.09.

The biggest decliner with a share price above $1 was Thousand Oaks agricultural biotech Ceres Inc., which has struggled since shifting its focus to genetically modified crops that can be used as biofuels. The company ended the year down 70 percent to $1.38.

Despite improved financials late in the year, Malibu toymaker Jakks Pacific Inc. ended the year down 46 percent to $6.72. Demand Media Inc. fell 38 percent to $5.77 as the Santa Monica operator of Internet media and domain services struggled with declining revenue.