Lower medical costs and the lack of large charges enabled Health Net Inc. to post a profit in the fourth-quarter compared with a loss a year ago.

The Woodland Hills health insurance company on Tuesday reported net income of $80.4 million (83 cents a share), compared with a net loss of $45.2 million (43 cents) a year earlier. Revenue fell 11 percent to $3.37 billion, which the company said was mostly due to the sale of the company’s Northeast business. The latest quarter included a litigation-reserve related benefit of $11.9 million.

Analysts surveyed by Thomson Reuters on average expected per-share profit of 78 cents on revenue of $3.36 billion.

“Our solid fourth quarter and full year 2010 results affirm that our ongoing efforts to sharpen the focus of the company continue to drive improved performance,” Chief Executive Jay Gellert said in a statement. “We believe we have had the best open enrollment commercial selling season in many years, and this supports our view that we will achieve commercial enrollment growth in 2011.”

Shares were up 63 cents, or 2 percent, to $29.16 in midday trading on the New York Stock Exchange.