Margin debt collated by the New York Stock Exchange peaked in February at $466bn and stood at $463bn in August. The peak in 2007 was $381bn. It hit a low of $173bn in early 2009. - http://www.ft.com/intl/cms/s/0/d4e4868a-5612-11e4-93b3-00144feab7de.html#axzz3GjGqIgf4