An analysis of 2007 income data published in the book "Creating an Opportunity Society" examined individuals according to three norms: a high-school diploma, a full-time job, and a marriage with a child born after the parents had reached 21. The book's authors found that 73.8% of people in families that followed all three norms had attained at least middle-class incomes, at the time considered to be $49,590-$82,650 for a family of three.
The data has been seen as a “three-step solution” to staying out of poverty, but the steps may be hard to reach for those already in poverty. Studies have demonstrated that social class is a significant predictor of a child’s educational success. A 2011 study found that low-income students were five times more likely to drop out of high school than high-income students.