The Los Angeles Business Journal’s index of largest local public companies made double digit gains in 2012.

The weighted LABJ Stock Index this year gained 12 percent to close at 134.57. Gainers outpaced decliners 110 to 70.

The two top gainers were Sequential Brands Group Inc., which soared 506 percent to $5, and Reed’s Inc., which jumped 412 percent to $5.68.

Sequential Brands, formerly known as People’s Liberation, benefitted from a reverse stock split and a change in business model from designer jeans maker to licensor of apparel brands. Specialty soda maker Reed’s reported its first-ever profitable quarter this summer, benefitting from wider national distribution and new products, such as its fermented kombucha probiotics drink.

The two top decliners were Cereplast Inc. of El Segundo, plunging 97 percent to 2 cents, and THQ Inc. of Agoura Hills, sliding 96 percent to 29 cents.

Cereplast, which supplies a resin primarily used to make eco-friendly plastic packaging, was hurt by the failure of an European expansion initiative. Video game maker THQ filed for Chapter 11 protection earlier this month as sales fell and the company retrenched.