The Los Angeles Business Journal’s index of the largest local public companies was flat for the week. The weighted LABJ index held steady at 235, with losers outpacing gainers 87 to 58. Thirteen companies closed the week unchanged.

Among stocks trading above $1, Pasadena prepaid debit card firm Green Dot Corp. was one of the week’s leading gainers. Shares spiked 31 percent to close at $19.95 on Friday after the company announced Monday it had signed a new five-year deal with Wal-Mart Stores Inc., by far its biggest retail partner.

MRV Communications Inc. was another winner this week. Shares of the Chatsworth provider of telecom equipment and services climbed 20 percent to close at $11.99. Major shareholder William Martin reportedly purchased 601,200 shares of stock in the company this week.

Cadiz Inc. was the week’s biggest loser. Shares of the water storage firm fell 11 percent to close at $8.66 Friday.