Covington-based Hornbeck Offshore Services said a slowdown in offshore drilling will force the company to idle an average of 11.4 of its 61 offshore service vessels in 2015.

The company’s active fleet will consist of an average of 45.9 offshore service vessels and 5.9 multipurpose supply vessels. The company offered the guidance as part of its fourth-quarter and 2014 earnings report.

Hornbeck’s fourth-quarter profit slipped to $19.2 million, or 53 cents per share, compared to $22.2 million, or 61 cents per share, a year ago

For the year, the company’s earnings dropped to $88.5 million, or $2.41 per share from $111.4 million, or $3.05 per share.

Results for the quarter and the year fell short of Wall Street’s forecasts. Analysts surveyed by Zacks Investment Research expected a fourth-quarter profit of 67 cents per share and $2.54 per share for the year.

Hornbeck said its results were lowered in part because of softness in the spot market for offshore services vessels.