The following chart from Avantis shows that concentration levels have increased dramatically in recent years, while the levels for the smaller-cap and value indexes have been relatively stable. Note ...

How can we assess concentration levels in a given index? A popular way to measure concentration levels in an index is by looking at the “effective” number of stocks in an index (also known as the ...

U.S. equity market concentration has increased sharply over the past decade as mega-cap companies have grown faster than the broader large cap universe. Measures such as the effective number of stocks ...