In 1907 and in 1908, the NYSE fell by nearly 50% due to a variety of factors, led by the manipulation of copper stocks by the Knickerbocker company.[21] Shares of United Copper rose gradually up to October, and thereafter crashed, leading to panic.[22][23] A number of investment trusts and banks that had invested their money in the stock market fell and started to close down. Further bank runs were prevented due to the intervention of J. P. Morgan.[24] The panic continued to 1908 and led to the formation of the Federal Reserve in 1913.[25]
For example, the United States has a set of thresholds in place to guard against crashes. If the Dow Jones Industrial Average (DJIA) falls 2,400 points (threshold 2) before 1:00 p.m., the market will be frozen for an hour. If it falls below 3,600 points (threshold 3), the market closes for the day. Other countries have similar measures in place. The problem with this method today is that if one stock exchange closes, shares can often still be bought or sold in other exchanges, which can cause the preventative measures to backfire.
Why Do They Call It Black Tuesday?
From October 6–10 the Dow Jones Industrial Average (DJIA) closed lower in all five sessions. Volume levels were record-breaking. The DJIA fell over 1,874 points, or 18%, in its worst weekly decline ever on both a points and percentage basis. The S&P 500 fell more than 20%.[36] The week also set 3 top ten NYSE Group Volume Records with October 8 at #5, October 9 at #10, and October 10 at #1.[37]