Hoku Corp. is being added to the Russell 3000 stock index, while Central Pacific Financial Corp. is being taken off as part of the annual reconstitution of the index.

The changes take effect Friday after the market closes.

Hoku, a Honolulu-based clean energy company, is one of 47 technology companies being added to the index, according to Russell Investments, which publishes a number of stock indexes. Hoku shares closed up 8 cents at $3.48 Monday on the Nasdaq exchange.

CPF, the parent of Central Pacific Bank, has struggled financially in recent years due to exposure to California homebuilders hit hard by the subprime lending meltdown. Shares of CPF fell 7 cents to close at $2.01 Monday . CPF shares were trading as high as $5 a year ago. Its market capitalization currently stands at $61 million.

Russell indexes are widely used by investment managers and institutional investors for index funds and as benchmarks for both passive and active investment strategies.