 During the first decade of the new century, growth was mainly concentrated in Montana's seven largest counties, with the highest percentage growth in Gallatin County, which had a 32% increase in its population from 2000–2010.The city having the largest percentage growth was Kalispell, with 40.1%, and the city with the largest increase in actual residents was Billings, with an increase in population of 14,323 from 2000–2010.On January 3, 2012, the Census and Economic Information Center (CEIC) at the Montana Department of Commerce estimated Montana had hit the one million population mark sometime between November and December 2011.