CHICAGO - Union Pacific Corp reported a lower quarterly profit on Thursday as slumping commodities prices and ailing industrial production hurt freight volumes, and the No. 1 U.S. railroad warned 2016 does not look much better for its business. The news sent the Omaha, Nebraska-based company’s shares down more than 7 percent to $68.20 in early trading. “Overall economic conditions, uncertainty in the energy markets, commodity prices, and the strength of the U.S. dollar will continue to have a major impact on our business this year,” Chief Executive Lance Fritz said in a statement. Executives said on a conference call with analysts they could not provide an earnings forecast for 2016 because of uncertainty in Union Pacific’s markets. The company said freight volumes dropped 9 percent during the fourth quarter, amid what industry executives have said is a “freight recession” for North American railroads. Last week, the No. 3 U.S. railroad CSX Corp reported a lower profit, and said a weak global economy and U.S. industrial markets would impact its 2016 results. Coal volumes plunged 22 percent during the quarter, continuing a downtrend trend afflicting the industry as utilities switch to burning cheaper natural gas and as a strong U.S. dollar hurts exports. Industrial products fell 16 percent in the quarter. Just this week, Moody’s Investors Service warned of “increasing risks of an industrial recession” for North American manufacturers. Union Pacific agricultural product volumes dropped 5 percent, reflecting an ongoing slump affecting farmers. Intermodal freight volumes, or shipments of consumer goods by container, fell 7 percent. The lone bright spot was automotive shipments, reflecting continued strong vehicle sales, which grew 8 percent. Although earnings were down, the railroad reported a healthy operating ratio, a key metric for analysts and investors, of 63.2 percent. This was due to efforts to reduce costs, as the railroad has furloughed 3,900 workers and put 1,400 locomotives in storage, as well as price increases for hauling freight. Union Pacific reported a quarterly net income of $1.1 billion, or $1.31 per share, down more than 21 percent from $1.4 billion, or $1.61 per share, a year earlier. Analysts had expected earnings per share for the quarter of $1.42. The company earned revenue of $5.2 billion, down more than 15 percent from $6.15 billion a year earlier. Analysts had expected revenue of $5.45 billion. Union Pacific said it planned to invest $3.75 billion on its network in 2016, down from $4.48 billion in 2015.