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The professional class, also called the upper middle class, consists mostly of highly educated white collar salaried professionals, whose work is largely self-directed. In 2005, these household incomes commonly exceed $100,000 per year.
Lower Middle Class. The lower middle class consists of mostly blue-collar workers who make just enough to distinguish themselves from the poor or lower class. The average income for lower middle-class households is $29,204 as of September 2012, compared with the lower-class average of $23,550 for a family of four.