http://www.davemanuel.com/median-household-income.php
http://articles.moneycentral.msn.com/SavingandDebt/LearnToBudget/TheSecretToSuccessInTheMiddleClass.aspx
AMERICAN UPPER CLASS:
"Households with net worths of $1 million or more may be identified as members of the upper-most socio-economic demographic, depending on the class model used. While most contemporary sociologists estimate that only 1% of households are members of the upper class, sociologist Leonard Beeghley asserts that all households with a net worth of $1 million or more are considered "rich""
http://en.wikipedia.org/wiki/American_upper_class
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