All the market focus has been on the Dow, but small caps beat the bigger index into a bear market. Even before the big falls of the last few days, the Russell was down 25%. Small companies account for about half of US economic activity and tend to feel the strongest effects when the economy falls, explaining the sharp decline. However, small caps also tend to outperform in the three months after such falls, as they also disproportionately benefit from an economic recovery.
FINSUM: Small caps were trading at all time highs right before this plunge, and as this situation begins to clear, it seems like a very good buying opportunity.