NEW YORK ( TheStreet) -- Norfolk Southern ( NSC) beat Wall Street's second-quarter profit expectations, keeping alive a streak of earnings outperformance from the railroad sector. Norfolk reported a bottom line of $392 million, or $1.04 a share, easily topping the Wall Street target of 99 cents. Revenue came to a little more than $2.4 billion, in line with consensus. Norfolk Southern saw a 22% increase in shipment volume in the second quarter. Sales in the railroad's biggest category of general merchandise rose 31% to $1.3 billion. Coal revenue, which just a few quarters ago was the major headwind for the rail sector, increased 36% for Norfolk Southern, the largest increase among its segments. A year ago, the company earned $247 million, or 66 cents a share. On Tuesday morning, Kansas City Southern ( KSU) also beat Wall Street expectations with a shipment increase of 35%, but its stock declined as the broader markets sold off and gains made by the rail shares over the past week were pared back. Kansas City Southern closed the session down 6%. Norfolk shares declined in after-hours trading Tuesday after falling 1% in the regular session, ending a rally that began Thursday, when better-than-expected results from Union Pacific ( UNP) and Canadian National Railways ( CNI) may have sparked heightened expectations for the rest of the rail sector. -- Written by Eric Rosenbaum from New York. Follow TheStreet.com on Twitter and become a fan on Facebook.