US railroad Norfolk Southern Corp reported higher quarterly results that beat analyst forecasts, sending its shares up nearly 5 percent, and forecast continued volume growth above the broader U.S. economy.

Higher pricing, fuel surcharges and a 3 percent volume increase drove profit higher in the third quarter.

The company said it benefited from tight truck capacity, as well as growth in the automobile, export coal and domestic intermodal businesses.

Intermodal refers to the shipment of goods in containers that can be moved from one form of transportation to another, such as from train to ship or train to truck.

"As we look ahead over the short term we continue to see signs pointing to overall, modest economic growth," Chief Executive Officer Wick Moorman told analysts on a post-earnings conference call. "And we anticipate that our overall volumes will continue to grow at a rate somewhat greater than that of the economy."

Norfolk Southern reported double-digit revenue increases in its coal, general merchandise and intermodal businesses in the quarter.

The company moved 23 percent more coal for export in the third quarter than a year ago and forecast ongoing strength into 2012.

About 55 percent of its coal exports went to Western Europe, about 20 pct to Asia and the rest to South America.

"We achieved record RPU (revenue per unit) levels in agriculture, metals and construction, paper, automotive and coal, surpassing the records previously set in each of these groups during the second quarter," Don Seale, chief marketing officer, said on the conference call.

Third-quarter net income rose 24 percent to $554 million, or $1.59 per share, from $445 million, or $1.19 per share, a year ago, the Norfolk, Virginia-based company said on Wednesday.

That beat the average analyst estimate of $1.41 a share, according to Thomson Reuters I/B/E/S.

Railway operating revenue rose 18 percent to $2.89 billion for the third-largest publicly held U.S. railroad company, compared with the average forecast of $2.87 billion.

Other big publicly held U.S. railroad companies -- Union Pacific Corp , CSX Corp and Kansas City Southern last week also reported higher quarterly profits.

Norfolk Southern operates about 20,000 route miles in 22 states and the District of Columbia and serves every major container port in the eastern United States. (Reuters)