Highmark, the insurance company whose subsidiary HVHC is the parent of Davis Vision, Viva International and Eye Care Centers of America, had a 9.2 percent increase in operating revenues to $13 billion in the first quarter, but its net income plunged by 74.9 percent to $94.1 million. Highmark said this was because of significantly lower investment income. The vision care operations had revenues of $1.2 billion, and the company noted that in 2008 this division served about a million more people than in 2007, covering almost 17 million customers.