Clark County is one of about 3,141 counties and county equivalents in the United States. It has 628.2 sq. miles in land area and a population density of 665.5 per square mile. In the last three decades of the 1900s its population grew by 168.8%. On the 2000 census form, 96.9% of the population reported only one race, with 1.7% of these reporting African-American. The population of this county is 4.7% Hispanic (of any race). The average household size is 2.69 persons compared to an average family size of 3.15 persons. In 2006 health care and social assistance was the largest of 20 major sectors. It had an average wage per job of $40,306. Per capita income grew by 7.1% between 1996 and 2006 (adjusted for inflation).

People & Income Overview (By Place of Residence)	Value	Rank in U.S.	Industry Overview (2006) (By Place of Work)	Value	Rank in U.S.
Population (2007)	418,070	155	Covered Employment	129,758	211
Growth (%) since 1990	75.6%	119	Avg wage per job	$38,019	359
Households (2000)	127,208	171	Manufacturing - % all jobs in County	10.5%	1630
Labor Force (persons) (2007)	211,038	159	Avg wage per job	$47,097	513
Unemployment Rate (2007)	5.6	801	Transportation & Warehousing - % all jobs in County	2.9%	1152
Per Capita Personal Income (2006)	$32,970	570	Avg wage per job	$40,696	839
Median Household Income (2005)	$51,124	319	Health Care, Social Assist. - % all jobs in County	12.5%	734
Poverty Rate (2005)	11.5	2163	Avg wage per job	$40,306	279
H.S. Diploma or More - % of Adults 25+ (2000)	87.8	267	Finance and Insurance - % all jobs in County	3.1%	938
Bachelor's Deg. or More - % of Adults 25+ (2000)	22.1	552	Avg wage per job	$51,305	305