Meanwhile, Colorado's population grew by 11 percent from 2009 to 2016, to 5.55 million residents.
State demographer Elizabeth Garner still expects the state's population to rise at a slow to moderate clip in the coming years.
- Colorado's population now stands at 5,546,574, up more than half a million from 2010.Read more
The migration of workers, mostly aged 25-34, has slowly moved the population center of the United States to Missouri. Soon that center could be in Colorado.