| County : | Clark County |
| State : | Illinois (IL) |
| Land Area : | 501.42 sq mi |
| Water Area : | 3.40 sq mi |
| Latitude : | 39.3323642 |
| Longitude : | -87.7916872 |
| Population (2010): | 16,335 |
| Population Estimate (2012) : | 16,353 |
| Population Density : | 32.58/sq mi |
| Housing Units (2012) : | 7,772 |
| Median Household Income (2012) : | $47,176 (Illinois : $56,853, USA : $53,046) |
| Median Family Income (2012) : | $53,586 (Illinois : $70,144, USA : $64,585) |
| Median House Price (2012) : | $86,300 (Illinois : $190,800, USA : $181,400) |
Clark County Cities / Towns
| Casey City (2,769) | Marshall City (3,933) | Martinsville City (1,167) |
| Westfield Village (601) | West Union (288) |
Clark County Zip Codes
| 61933 (1,141) | 61944 (12,908) | 62413 (421) |
| 62420 (4,759) | 62423 (724) | 62441 (7,395) |
| 62442 (2,421) | 62449 (3,175) | 62474 (848) |
| 62477 (946) | 62478 (398) |