| In October 2006, the United States Census | | | | |
| Bureau released data about the median family | | | | 10. Montgomery County - $98,662 (Maryland) |
| income of families in all counties within the | | | | |
| United States and Puerto Rico. The data was | | | | 11. Williamson County - $95,470 (Tennessee) |
| released in the Bureau's Annual Community | | | | |
| Survey (ACS) report. The median family income | | | | 12. Calvert County - $93,842 (Maryland) |
| (in 2005 Inflation-Adjusted Dollars) | | | | |
| represents the mid-point of family income for | | | | 13. Monmouth County - $92,080 (New Jersey) |
| a county, where half of the families are | | | | |
| above the median value, and half of the | | | | 14. Nassau County - $91,349 (New York) |
| families are below the median value. The | | | | |
| median value measurement is sometimes a | | | | 15. Rockland County - $90,947 (New York) |
| better indicator than average value because | | | | |
| it is less susceptible to unusually high or | | | | As noted above, Virginia occupied the top 3 |
| low values. | | | | slots on this list. New Jersey had 4 counties |
| | | | within the top 15. Maryland had three |
| Listed below are the top 15 counties with the | | | | counties in the top 15. New York had 2 |
| highest median family income, followed by the | | | | counties in the top 15. Surprisingly, |
| median value dollar amount, and the State. | | | | California only had 1 county in the top 15, |
| | | | which was Marin County located just north of |
| 1. Loudoun County - $110,910 (Virginia) | | | | San Francisco. The median family income for |
| | | | United States as a whole was $58,832. |
| 2. Fairfax County - $110,107 (Virginia) | | | | |
| | | | If you are interested in buying a home, condo |
| 3. Arlington County - $106,218 (Virginia) | | | | or townhouse or any other type of real |
| | | | estate, you should know that the median |
| 4. Hunterdon County - $106,167 (New Jersey) | | | | family income of a region is sometimes used |
| | | | by lenders to determine if a family is |
| 5. Somerset County - $105,872 (New Jersey) | | | | eligible for special low-income loan |
| | | | programs. |
| 6. Howard County - $103,390 (Maryland) | | | | |
| | | | For detailed ranking tables of all counties |
| 7. Morris County - $100,971 (New Jersey) | | | | within the United States, visit the Census |
| | | | Bureau's web site, and select the most recent |
| 8. Marin County - $99,713 (California) | | | | American Community Survey report. The |
| | | | American Community Survey report is published |
| 9. Douglas County - $99,531 (Colorado) | | | | annually. |