Schlumberger Ltd. said Friday that its third-quarter profit fell 25 percent when compared with year-ago results fattened by a $1.27 billion investment gain.

Its adjusted earnings fell short of Wall Street expectations, and its shares fell $2.34, or 3.4 percent, to $65.65 in premarket dealings.

The Houston oil services company reported its net income fell to $1.3 billion, or 96 cents per share, for the July-September quarter. That compares with $1.73 billion, or $1.38 per share, a year ago.

Excluding special charges and credits, Schlumberger said income from continuing operations was 98 cents per share.

That fell short of Wall Street estimates. Analysts, who typically exclude special items, had expected adjusted earnings of $1.01 per share.

Revenue rose 49.4 percent to $10.2 billion from $6.85 billion a year ago. That matched Wall Street expectations.

The company said the "current financial turmoil" in the global economy has lowered the outlook for oil demand growth in 2012 although it is still expected to top that of this year.

It said it was "confident that any reductions will be short-lived, and that the outlook for the service industry remains very positive."