Recently, I put together a study of market volatility. The study used the daily New York Stock Exchange (NYSE) advance-decline data going back to 1970. Advance-decline data simply looks at the number of stocks advancing (increasing) and the number of stocks declining in value. What I looked for was outsized ratios of daily advance-decline data. A ratio over 9:1, whether it be advancers to decliners or decliners to advancers is considered outsized. The results are below. Hmmm…
