Hawaiian Telcom today reported an 18 percent decline in second quarter earnings, which it a attributed primarily to an increase in costs associated with the expansion of its broadband network.

The state’s largest phone company reported net income of $5.5 million, or 51 cents a share, in the April-to-June quarter, down from $6.7 million, or 61 cents a share, in the same period a year earlier.

Revenue totaled $94.7 million in the second quarter, down from $100.7 million a year earlier. Hawaiian Telcom reported a 5 percent year-over-year increase in business data revenue driven by growth in switched ethernet, IP-VPN and dedicated internet services.

The company also continued to expand its internet television produce launched in July 2011. The number of subscribers increased to about  6,400 by the end of the second quarter from 3,700 at the end of the first quarter, according to Hawaiian Telcom.

“I am pleased with the momentum we are starting to build in key growth areas of our business,” said Eric Yeaman, Hawaiian Telcom chief executive officer. “Our early success demonstrates the strong customer demand for our video product and positions us well to drive further growth in consumer revenues,” he said.

Hawaiian Telcom’s shares were up 22 cents at $18.62 in late trading on the Nasdaq Global Market.