CSX Corp (CSX.O), the third-largest U.S. railroad operator, reported a slight rise in quarterly net profit that met analyst expectations on Tuesday, on revenue lifted by shipment of coal and consumer goods and higher freight rates.

The Jacksonville, Florida-based railroad posted third-quarter net income of US$459 million, or 51 cents US per share, up from US$455 million, or 48 cents US per share a year earlier.

The results sent CSX shares up marginally in premarket trading by 22 cents US to US$53.06.

CSX has struggled with persistent customer complaints of service disruptions since the summer as its new Chief Executive Hunter Harrison worked to implement a controversial strategy overhaul to revamp the railroad's network.

The company's freight volumes were up one per cent in the quarter, driven by five-per-cent gains in both coal and consumer goods shipments which offset declines in almost every other commodity the railroad hauls, such as vehicles and fertilizer.

CSX's revenue grew one per cent to US$2.74 billion, from US$2.71 billion, but was short of analyst expectations of US$2.77 billion.

CSX reported an operating ratio, which measures operating costs as a percentage of revenue, of 68.1 per cent, down from 69 per cent. A lower operating ratio shows improvement in profitability and is a key metric for Wall Street.