Emboldened by soaring stock prices and record-low borrowing costs, stock investors are taking out loans against their portfolios at the fastest pace since before the Great Recession hit.
So-called margin debt hit $379.5 billion in March, the highest level since July 2007 when such debt hit an all-time record of $381.4 billion, according to the most recent data available compiled by the New York Stock Exchange.
The trend signals that investors are more comfortable with stocks and are more willing to use borrowed money to buy more securities in hopes of garnering fatter returns in a hot market that has pushed the Dow Jones industrials up more than 15 percent in 2013.
But there's also a dark side: The use of borrowed money also could be signaling that risk-taking is becoming extreme and that investor enthusiasm is becoming too bullish, which could set those investors and the market up for disappointment if stocks turn south.
In short, rising margin debt could also be a sign of growing investor complacency.
"Margin debt is now (near) record levels," says Bruce Bittles, chief investment strategist at R.W. Baird. "When investors are willing to borrow lots of money to buy stocks, that is a sign of real optimism."
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Bittles adds, "At important points in the stock market, investor sentiment typically is the best guide."
But he says margin debt is just one aspect of the overall sentiment picture. He notes that the latest weekly poll of its members by the American Association of Individual Investors found more bears than bulls, a sign that sentiment is not yet at irrationally exuberant levels.
Still, current margin debt levels are 28 percent higher than they were in March 2012, and nearly 36 percent higher than at the market peak in March 2000.
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The past two times margin debt peaked in 2007 and 2000 it was also a sign of a stock market top, data show.