I'm sure the folks at UnitedHealth Group (NYSE:UNH) are happy to have 2008 behind them. Rising health-care costs and a higher unemployment rate -- and therefore more uninsured people -- is a bad combination for health insurers.

The company capped off the year with another quarter of sinking earnings, but everyone saw that coming. Earnings per share fell 15% after adjusting for the previously announced charges, bringing the adjusted net earnings for the year to $2.95. Compare that to the $3.95 to $4.00 per share that the company was predicting it would earn this time last year and you can see just how bad a year it was.

Revenue in the fourth quarter was actually up 9%, but unfortunately the company's costs rose even faster. The medical care ratio -- medical costs divided by premiums -- jumped to 80.8% in the fourth quarter from 79.9% last year. But that's still an improvement compared to earlier in the year when the medical ratio was increasing at alarming rates.

There was some good news for UnitedHealth in 2008: Things could have been a whole lot worse. Insurers have a large stash of investments in bonds and other interest-paying investments like mortgage-backed securities that could have caused a bad blow-up -- think AIG (NYSE:AIG) bad. Considering how bad the economy was last year, investors should be pretty happy with the relatively minor losses that Aetna (NYSE:AET) and Humana (NYSE:HUM) reported.

For this year, UnitedHealth is looking for earnings of $2.90 to $3.15 -- essentially flat compared to last year. That doesn't seem so bad, considering that it's expecting to lose as many as 1.5 million members as the unemployment rate grows.

Like rivals Aetna, Cigna (NYSE:CI), and WellPoint (NYSE:WLP), UnitedHealth is trading at a P/E in the single digits -- multiples that were unheard of in years past. But with the non-existent growth this year and the uncertainty that President Obama brings, it seems that they're destined to stay this cheap until the growth returns and a little more is known about the future of universal health care.

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WellPoint and UnitedHealth are Motley Fool Inside Value recommendations. UnitedHealth is a Motley Fool Stock Advisor selection. The Fool owns shares of UnitedHealth Group. Try any of our Foolish newsletters today, free for 30 days.

Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool has a disclosure policy.