The S&P 500 (SNPINDEX: ^GSPC) declined 12% in five trading days in early April, erasing more than $6 trillion from the U.S.

VIX, or the CBOE Volatility Index, is fluctuating around 30, a level that indicates moderately high market stress.

A sharp drop in volatility suggests the weekslong stock market sell-off may be over. A decline in the VIX below 30 after surging above 50 indicates a "bear killer" signal, a technical analyst says.

Since 1990, after the VIX breached 50, it averaged a gain of 32% over the next year and a gain of 48% over the next two years. Of course, the sample size there is two. But even when the VIX traded ...

Stock market volatility peaked when the CBOE Volatility Index (VIX) reached 52.3 on April 8, one of the highest readings since January 1990. The S&P 500 has typically skyrocketed during the year ...