Meanwhile, equity markets are shrinking: market capitalisation measures show that the markets are generally rising, but this is from fewer and fewer companies. The shrinkage is caused largely by the buy-back market in the US over the past 10 years which has been greater, at $5 trillion, than the amount of quantitative easing by the Federal Reserve. In addition, some firms fold or merge and there is a shortage of initial public offerings. It is becoming more difficult for private equity to find companies to buy out.