"Margin debt is a function of the value of the investment portfolio. If the value of the portfolio declines, the investor is forced to sell in order to comply with the margin requirements. Just like in 2007/08 and 2000/01, a “return to normality” will mean heavy and sudden declines of stock indices.............................. When interest rates are raised little by little, this will lead to upheaval in the financial markets. Former Fed chairman Alan Greenspan subscribes to this conclusion........................... Keep an eager eye on the Federal Reserve balance sheet his year. It may give you a loud and clear signal about the turning point in the market. The turning point at which the stock market crashes, the economy gets into trouble and gold becomes the stock market’s favorite once more." https://www.goldrepublic.com/news/what-central-banks-did-in-2014-and-will-do-in-2015.html