The New York Stock Exchange (NYSE) tracks margin debt for the US market. The April 2013 figure of USD384bn marked an all-time high since records started in 1959!. When netting out account credit metrics, such as Free Credit Cash and Credit Balances in margin accounts, total investor net worth just hit a record low since 2000 at USD106bn. In short, investors have rarely been more levered than today!
MOM changes of >10% in NYSE Margin Debt levels precede S&P500 peak by 3mos.