RANKING · 1990 CENSUS · 102 SHOWN OF 102

Oldest by median age, Illinois counties · 1990

Illinois counties ranked by median age of residents (1990 ACS). This list covers the 102 counties in Illinois that qualify, ranked against each other statewide.

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SAME RANKING BYCities States Metros ZIP codes

RELATEDLargest foreign-born population Most residents with a disability Largest veteran population Most uninsured people Largest senior population Most unmarried people

YEAR1990 2000 2010 2020 2024

RANKPLACESTATEPOPMEDIAN AGEVS –

01Gallatin County, ILIL4,61640.0–

02Hamilton County, ILIL7,85939.5–

03Saline County, ILIL22,77238.3–

04White County, ILIL13,25038.3–

05Calhoun County, ILIL4,30038.3–

06Franklin County, ILIL36,91638.0–

07Union County, ILIL16,65638.0–

08Massac County, ILIL13,50237.9–

09Stark County, ILIL5,31937.8–

10Lawrence County, ILIL13,79037.8–

11Schuyler County, ILIL6,65737.7–

12Pike County, ILIL14,23137.7–

13Marshall County, ILIL11,47337.6–

14Henderson County, ILIL5,98437.6–

15Edgar County, ILIL16,32337.5–

16Edwards County, ILIL5,89837.5–

17Hancock County, ILIL16,80337.4–

18Carroll County, ILIL15,41937.4–

19Hardin County, ILIL3,58837.3–

20Wayne County, ILIL15,88237.3–

21Iroquois County, ILIL26,15037.1–

22Crawford County, ILIL18,64837.0–

23Fulton County, ILIL32,90136.9–

24Clark County, ILIL15,11436.9–

25Clay County, ILIL12,79336.8–

26Moultrie County, ILIL14,37136.7–

27Ford County, ILIL13,21636.6–

28Mason County, ILIL12,41136.5–

29Christian County, ILIL33,44336.4–

30Knox County, ILIL47,76736.3–

31Bureau County, ILIL32,51036.2–

32Jo Daviess County, ILIL21,59436.2–

33Shelby County, ILIL20,57636.2–

34Williamson County, ILIL67,22536.1–

35Mercer County, ILIL15,22936.1–

36Piatt County, ILIL16,79136.1–

37Greene County, ILIL11,31336.0–

38Macoupin County, ILIL43,74836.0–

39Putnam County, ILIL5,61935.9–

40Scott County, ILIL4,86635.9–

41Henry County, ILIL48,09535.9–

42Washington County, ILIL13,56435.9–

43Adams County, ILIL64,26735.8–

44Cass County, ILIL12,46335.8–

45Pope County, ILIL3,67235.6–

46Richland County, ILIL15,21935.6–

47Johnson County, ILIL13,36335.5–

48Vermilion County, ILIL71,25935.5–

49LaSalle County, ILIL107,77335.5–

50Menard County, ILIL11,86335.4–

51Perry County, ILIL20,16035.4–

52De Witt County, ILIL15,11835.4–

53Montgomery County, ILIL28,07635.3–

54Fayette County, ILIL20,79035.3–

55Warren County, ILIL16,22235.2–

56Marion County, ILIL36,38235.1–

57Bond County, ILIL16,95935.0–

58Macon County, ILIL99,30035.0–

59Stephenson County, ILIL43,22035.0–

60Rock Island County, ILIL141,86935.0–

61Wabash County, ILIL10,90735.0–

62Pulaski County, ILIL4,82034.9–

63Jefferson County, ILIL36,14734.9–

64Whiteside County, ILIL54,12134.8–

65Tazewell County, ILIL130,04934.8–

66Alexander County, ILIL4,57034.7–

67Logan County, ILIL27,18234.6–

68Jasper County, ILIL9,03234.5–

69Douglas County, ILIL19,88034.5–

70Morgan County, ILIL32,51534.5–

71Lee County, ILIL32,91434.3–

72Sangamon County, ILIL194,17034.3–

73Livingston County, ILIL35,05734.3–

74Woodford County, ILIL38,11134.1–

75Randolph County, ILIL29,92134.0–

76Monroe County, ILIL34,84034.0–

77Madison County, ILIL263,11034.0–

78Ogle County, ILIL51,39934.0–

79Peoria County, ILIL178,55333.9–

80Cumberland County, ILIL10,20833.8–

81Winnebago County, ILIL283,67433.5–

82Brown County, ILIL6,40133.5–

83Grundy County, ILIL54,05233.3–

84Jersey County, ILIL21,16033.2–

85Boone County, ILIL53,56833.2–

86Kankakee County, ILIL105,52532.9–

87Clinton County, ILIL37,12832.9–

88Cook County, ILIL5,194,62532.8–

89DuPage County, ILIL934,29832.4–

90McHenry County, ILIL317,75132.4–

91St. Clair County, ILIL250,70832.2–

92Kendall County, ILIL145,47032.2–

93Effingham County, ILIL34,51931.9–

94Lake County, ILIL719,33931.7–

95Will County, ILIL712,25331.2–

96Kane County, ILIL525,75730.9–

97Coles County, ILIL46,60729.9–

98McLean County, ILIL171,41929.1–

99Champaign County, ILIL209,97227.8–

100McDonough County, ILIL25,91627.4–

101DeKalb County, ILIL101,83527.3–

102Jackson County, ILIL52,50126.5–

SHOWING 1–102 OF 102

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU DECENNIAL CENSUS