Over recent years, the index has performed even better than usual, as it has rewarded the success of rapidly growing Big Tech companies. But the U.S. stock market’s concentration by market ...

The S&P 500 Is Doing Something That Hasn't Been Seen in Nearly 100 Years. Here Are the 10 Most Important Stocks to Keep an ...

While stock market concentration raises legitimate concerns, the historical performance of passive index funds compared to active management suggests that the issue may not be as dire as some fear.

In the 1960s, by contrast, when the market was more concentrated, the top five stocks by weighting were in different sectors. When companies representing high concentration in an index correct ...