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# A middle range income. What is considered "middle range" can be quite broad, especially since most Americans yearn to be known as "middle class". Though an average yearly income in the United States is about $30,000, incomes all the way from $20,000 up to $75,000 a year are generally considered middle class. Around 1980, when asked what level of personal income would qualify as middle-class, George H. W. Bush replied: $50,000. In fact, only 5 percent of the U.S. population was making that level of income at the time.

# A net worth- what a person's total material assets are worth, minus their debt. Most economists define "middle class" citizens as those with net worths of between $25,000 (low-middle class) to $250,000. Those with net worths between $250,000 and $500,000 typically are categorized as upper-middle-class.

More at http://en.wikipedia.org/wiki/Middle_class