Health Net Inc. announced new guidance on Thursday that increases its 2015 earnings outlook by 30 percent compared to this year. The Woodland Hills insurer expects net income of at least $2.55 a share next year, compared to guidance of $1.95 for this year. Revenue is projected to hit $17.4 billion, an increase of nearly 23 percent compared to its 2014 guidance. It also plans for membership in its health plans to grow 8.2 percent to 3.5 million people. Health Net has aggressively sought market share by attracting formerly uninsured people who are entering the health system through the Affordable Care Act. During the most recent quarter, it added 609,000 subscribers to its health plans. The company also announced that its board has approved a $258 million increase to the company’s existing share repurchase program. Including the newly authorized money, Health Net currently has authority to spend $400 million on repurchases. Shares closed up $2.56, or 4.9 percent, to $54.34 on the New York Stock Exchange.