UnitedHealth (UNH) projected a 5% increase in 2013 earnings on Monday, but Wall Street had been anticipating stronger growth from the largest U.S. private health insurer.

Shares of the newest member of the Dow Jones Industrial Average retreated about 1% in the wake of the weaker-than-expected guidance.

A day before its annual investor conference in New York, UnitedHealth forecasted 2013 EPS of $5.25 to $5.50, which is well below the Street’s view of $5.58.

Management also forecast 2013 revenue of $123 billion to $124 billion, compared with consensus calls from analysts for $119.12 billion.

For the current year, UnitedHealth reaffirmed its prior outlook for EPS of $5.20 to $5.25. Even the high end of that new range would trail the Street’s view of $5.27.

Wall Street reacted somewhat negatively to the new outlook from UnitedHealth, driving shares of the Minnetonka, Minn.-based company down 0.96% to $53.40 in premarket trading. The stock has gained about 6% so far this year, underperforming the broader markets, and 23% over the past 12 months.

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