Constellation Energy (CEG) revealed on Friday a worse-than-expected decline in fourth-quarter profit, driven primarily by higher operating and maintenance costs as well as increased storm-related expenses and inflation.

The Baltimore-based company posted net income of $158.8 million, or 79 cents a share, compared with $4.4 billion, or $21.96 a share, in the same quarter last year.

Excluding one-time items, the company earned 42 cents a share, falling short of average analyst estimates polled by Thomson Reuters of 59 cents.

Revenue for the provider of nuclear, gas and electric energies was $3.47 billion, up slightly from $3.4 billion a year ago.

“We ended 2010 having completed all of the strategic initiatives we announced at the start of the year, successfully putting our core businesses in a stronger position to operate more efficiently, strengthen existing customer relationships and win new business,” said Constellation Energy CEO Mayo Shattuck.

Constellation reaffirmed its 2011 earnings guidance in the range of $3.10 to $3.40 a share.

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