Rockwell International Corp. said earnings rose a better-than-expected 13% in its fiscal third quarter as efficiency improvements offset soft sales in some core markets. The results pushed Rockwell's shares up $3.31, or nearly 10%, to close at $37.50 on the New York Stock Exchange. Rockwell's net income grew to $170 million, or 90 cents a share, from $150 million, or 77 cents, a year ago, as sales edged up 1.8% to $1.82 billion. Analysts on average had expected 87 cents a share, according to First Call/Thomson Financial. Rockwell said its global market leadership position and ongoing streamlining efforts boosted operating margins in both the automation and avionics and communications sectors. Slower demand for products such as factory floor and communications devices, due to a general slump in the paper, metals and petrochemical industries, checked revenue in the automation unit, its largest division, the company said. The unit achieved modestly higher sales as increased shipments in Europe, Asia Pacific and Canada offset sluggish markets in the United States, the company said.