Since April, the US stock market has entered a downward cycle. The S&P 500 fell from 4545.86 points on April 1 to the current 4287.50 points, a decline of 7.43%; the NASDAQ fell much more, from 14532.55 points in early April to 12790.74 points, a drop of nearly 12%, the collective decline within the US stock market made the market's panic index soar.