1930s: On October 28, 1929, the stock market loses 12.8 percent of its value. The event, dubbed "Black Thursday" results in widespread panic, numerous bank failures, and precipitates the great depression, which lasts throughout the 1930s.

1997: On October 27, the stock market loses 7.2 percent of its value, with the biggest one-day point loss in history. Computers automatically shut down the market to prevent panic. Despite the shocking decline, caused by unstable Asian markets, the New York Stock Exchange rebounds significantly in the next day of trading.

1930s: Alcoholism is not a well-understood disease. Individuals deal with the condition to the best of their own ability. Alcoholics Anonymous, the first substantial effort to address the problem, is organized by Bill Wilson in New York City in 1935. The program is a self-help fellowship designed to empower alcoholics to control their drinking habits.

1990s: Alcoholics Anonymous has more than 30,000 local groups...