Union County, Kentucky (Formed 1811)
                Land Area          
Year  Population  (sq.mi)   Density
2010     15,007     342.9     43.8
2000     15,637     345.1     45.3
1990     16,557     345.1     48.0
1980     17,821     345.1     51.6
1970     15,882     345.1     46.0
1960     14,537     345.1     42.1
1950     14,893     345.1     43.2
1940     17,411     345.1     50.5
1930     17,053     345.1     49.4
1920     18,040     345.1     52.3
1910     19,886     325.0     61.2
1900     21,326     387.0     55.1
1890     18,229     387.0     47.1
1880     17,809     357.2     49.9
1870     13,640     357.2     38.2
1860     12,791     357.8     35.7
1850      9,012     418.3     21.5
1840      6,673     417.3     16.0
1830      4,764     417.3     11.4
1820      3,470     417.3      8.3