The following table details U.S. median household income by county from the 2005-2009 American Community Survey from the U.S. Census Bureau. Counties where the margin of error exceeded $2,000 have been excluded.
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2005-2009 Census 2000
County Name ACS Income Income Change
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Loudoun County, Virginia $112,021 $103,817 $8,204
Fairfax County, Virginia $104,259 $104,335 -$76
Howard County, Maryland $101,003 $95,474 $5,529
Douglas County, Colorado $99,522 $106,754 -$7,232
Morris County, New Jersey $96,316 $99,559 -$3,243
Somerset County, New Jersey $96,233 $99,035 -$2,802
Arlington County, Virginia $93,806 $81,101 $12,705
Nassau County, New York $92,450 $92,724 -$274
Montgomery County, Maryland $92,213 $92,107 $106
Stafford County, Virginia $90,586 $86,003 $4,583