A generally rising stock market tends to boost most stock prices, but the amount of lift can vary widely.
Through most of the last five years, the market focused mostly on the largest growth stocks that largely were responsible for the S&P 500 outperforming many other market measures. Although it was not completely ignored, the Russell 2000 small cap
index lagged the S&P 500 and Dow Jones Industrial Average (DJIA).
In the previous five years, the appreciation rate in the Russell 2000 was 32% less than for the DJIA and the S&P 500. As the S&P 500 in the middle of this month threatened to regain its all-time high, the Russell 2000 rushed higher to narrow this gap.