John J. Koraleski, executive vice president-Marketing and Sales, will serve as acting president and CEO during Young's absence.
Steven Rogel, Union Pacific's lead independent director, said: "The board has a great deal of confidence in Jack, Rob Knight our CFO, Lance Fritz our head of operations, and the entire management team. We are confident that our company will continue to provide great service to our customers while meeting the financial and safety objectives we have set for ourselves and our shareholders expect."
Since joining the railroad in 1972, Koraleski has held a number of executive positions including controller of Union Pacific Corp. and executive vice president-finance and chief financial officer of Union Pacific Railroad. He also has held positions in the railroad's information technologies, real-estate, and administrative departments. He earned both a bachelor's and master's degree in business administration from the University of Nebraska at Omaha.