All categories of employment showed increases year-over-year.
The largest employment group, transportation (train and engine), increased 3.75% to 64,397. The second largest, maintenance of way and structures, was up 2.57% to 35,503. The number of maintenance of equipment and stores workers rose 4.40% to 29,791.
Other employment groups posted these numbers: Executives, officials, and staff assistants, 9,472, up 3.25%; Professional and administrative, 13,800, up 2.42%; and Transportation (other than train and engine), 6,754, up 3.34%.
The Class I employment index, based on 1967 as 100, rose to 27.1 in December 2011, compared with 26.2 in December 2010 and 24.9 in December 2009.