The Los Angeles Business Journal’s index of largest local public companies closed up slightly at the end of last week of a tumultuous year for the stock market.

The weighted LABJ Stock Index closed up 0.49 percent to 120.06 for the week ended Dec. 30. Decliners outpaced gainers 86 to 80, with seven companies unchanged.

Among the biggest gainers was Virco Manufacturing Corp. in Torrance, which jumped 19 percent to $1.61. The Torrance maker of business and school furniture, which recently went through layoffs, announced a new line of credit.

Response Genetics Inc. rose 14.6 percent to $1.53. The Los Angeles maker of cancer diagnosic tests named a new chief executive.

Broadway Financial Corp. gained 10 percent to $1.56. The South L.A. thrift announced it had regained compliance with Nasdaq listing requirements.

Among the largest decliners was MannKind Corp. which fell 9 percent to $2.50. The Valencia biotech’s stock has been punished since January, when the U.S. Food and Drug Administration delayed approval of its inhaled insulin product and required additional clinical trials.

RealD Inc. fell 8 percent to $7.94. Shares of Beverly Hills developer of 3-D movie technology have been volatile over concerns that moviegoers were less inclined to pay a premium for 3-D versions of any film.