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 676.1 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 2007 health care and social assistance was the largest of 20 major sectors. It had an average wage per job of $42,259. Per capita income grew by 4.5% between 1997 and 2007 (adjusted for inflation).

People & Income Overview (By Place of Residence)	Value	Rank in U.S.	Industry Overview (2007) (By Place of Work)	Value	Rank in U.S.
Population (2008)	424,733	155	Covered Employment	132,548	208
Growth (%) since 1990	78.4%	121	Avg wage per job	$39,464	371
Households (2000)	127,208	171	Manufacturing - % all jobs in County	10.3%	1618
Labor Force (persons) (2008)	214,826	157	Avg wage per job	$49,470	485
Unemployment Rate (2008)	6.9	797	Transportation & Warehousing - % all jobs in County	3.0%	1101
Per Capita Personal Income (2007)	$34,426	663	Avg wage per job	$42,788	712
Median Household Income (2007)	$58,167	262	Health Care, Social Assist. - % all jobs in County	12.5%	748
Poverty Rate (2007)	9.5	2608	Avg wage per job	$42,259	262
H.S. Diploma or More - % of Adults 25+ (2000)	87.8	267	Finance and Insurance - % all jobs in County	2.9%	1086
Bachelor's Deg. or More - % of Adults 25+ (2000)	22.1	552	Avg wage per job	$51,155	363