The Russell 2000, which is composed of medium-sized US-based firms serving mostly US customers is up by 4.5% over the past two years. This compares with +16.5% for the S&P 500 and +25.5% for the NASDAQ, which are far more globally oriented. (These are capital changes figures, which I plucked off Yahoo Finance.)
The latter two are 3.7x and 5.7x the return on the Russell 2000. Attention grabbing, yes, but not the right way to sum up the situation. More important is that these ratios happen because ex dividends the Russell has returned pretty close to zero.