BETHESDA, Md. ( TheStreet) -- Lockheed Martin ( LMT - Get Report), the defense company, said first-quarter earnings fell 18% as it recorded a charge from changes to health care legislation.

Lockheed said earnings were $547 million, or $1.45 a share, down from year-earlier earnings of $666 million, or $1.68 a share. The latest quarter included a charge of $96 million, or 25 cents a share, from legislation that eliminates the tax deduction for benefit costs reimbursed under Medicare Part D.

Analysts surveyed by Thomson Reuters forecast Lockheed would earn $1.34 a share in the first quarter.

Lockheed also reduced its earnings outlook for 2010 by a total of 15 cents a share to $7 to $7.20 a share, taking into account the Medicare charge of 25 cents a share and an improvement of 10 cents a share in the company's outlook primarily because of higher investment income.

-- Reported by Joseph Woelfel in New York.

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