FILE- In this July 20, 2017, file photo, a Union Pacific employee is seen on board a locomotive in a rail yard in Council Bluffs, Iowa. Union Pacific Corp. reports earns on Thursday, April 26, 2018. (AP Photo/Nati Harnik, File)

FILE- In this July 20, 2017, file photo, a Union Pacific employee is seen on board a locomotive in a rail yard in Council Bluffs, Iowa. Union Pacific Corp. reports earns on Thursday, April 26, 2018. (AP Photo/Nati Harnik, File)