RANKING · 2010 CENSUS · 63 SHOWN OF 63

Fastest shrinking, Colorado counties · 2010

Colorado counties with the steepest population decline since the prior decennial census. This list covers the 63 counties in Colorado that qualify, ranked against each other statewide.

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SAME RANKING BYCities States Metros

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YEAR2000 2010 2020

RANKPLACESTATEPOPPOPULATION GROWTHVS 2000

01Cheyenne County, COCO1,713-17.7%+156%

02Baca County, COCO3,347-16.1%+1785%

03Huerfano County, COCO7,011-14.6%−147%

04Mineral County, COCO910-14.3%−129%

05Kiowa County, COCO1,412-13.8%+253%

06Sedgwick County, COCO2,247-13.4%−732%

07Prowers County, COCO11,884-13.3%−257%

08Jackson County, COCO1,211-11.6%+565%

09Lincoln County, COCO5,645-10.2%−130%

10Otero County, COCO17,683-7.3%−1267%

11Lake County, COCO7,552-6.4%−121%

12Costilla County, COCO3,679-3.8%−126%

13Rio Grande County, COCO11,087-3.5%−123%

14Clear Creek County, COCO8,994-2.5%−111%

15Washington County, COCO4,732-2.3%−196%

16Conejos County, COCO7,529-1.7%−113%

17Phillips County, COCO4,420-0.8%−112%

18Boulder County, COCO328,560+1.1%−96%

19Jefferson County, COCO580,451+1.4%−93%

20Fremont County, COCO50,039+1.5%−97%

21Las Animas County, COCO14,391+2.0%−81%

22Yuma County, COCO9,896+2.1%−79%

23Alamosa County, COCO16,688+3.2%−68%

24Saguache County, COCO6,732+3.2%−89%

25Kit Carson County, COCO7,069+3.2%−73%

26Morgan County, COCO30,306+3.6%−85%

27Moffat County, COCO13,122+4.6%−71%

28Crowley County, COCO5,677+5.5%−86%

29Hinsdale County, COCO753+6.7%−90%

30Montezuma County, COCO26,678+7.2%−74%

31Denver County, COCO740,613+8.2%−56%

32Bent County, COCO5,716+8.4%−56%

33Chaffee County, COCO20,831+9.6%−66%

34Gunnison County, COCO17,439+9.8%−73%

35Logan County, COCO20,654+10.8%−36%

36Delta County, COCO32,178+11.2%−66%

37Rio Blanco County, COCO6,683+11.4%+4746%

38Park County, COCO18,314+11.6%−89%

39San Miguel County, COCO7,753+11.6%−86%

40Dolores County, COCO2,466+11.9%−47%

41Pueblo County, COCO169,277+12.4%−17%

42Teller County, COCO24,756+13.6%−79%

43Gilpin County, COCO6,073+14.4%−74%

44Pitkin County, COCO16,625+15.3%−12%

45Elbert County, COCO30,534+16.2%−85%

46La Plata County, COCO56,898+16.8%−53%

47Arapahoe County, COCO673,820+17.2%−30%

48Ouray County, COCO5,265+18.5%−71%

49Summit County, COCO31,517+18.9%−77%

50Larimer County, COCO377,292+19.1%−45%

51Grand County, COCO16,496+19.3%−66%

52Routt County, COCO25,329+19.4%−51%

53El Paso County, COCO757,040+20.4%−33%

54Adams County, COCO554,668+21.4%−43%

55Custer County, COCO5,590+21.5%−74%

56Archuleta County, COCO14,306+22.1%−74%

57Montrose County, COCO44,591+23.5%−36%

58San Juan County, COCO813+25.3%−201%

59Eagle County, COCO54,291+25.3%−72%

60Mesa County, COCO162,845+26.2%+6%

61Garfield County, COCO63,474+28.8%−38%

62Weld County, COCO378,426+39.7%+7%

63Douglas County, COCO399,396+62.4%−67%

SHOWING 1–63 OF 63

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UPDATED 2026-06-02 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES