"Some index funds rely on sampling to save on trading costs," Criscuolo says. "Sampling can introduce tracking error, positive or negative, into a fund's performance. Similarly, funds that track ...

Volatile prices and high inflows impact gold and silver ETFs, affecting tracking error and overall investor returns.

Passive funds aim to mirror their benchmark indexes as closely as possible, making every basis point matter. But perfect tracking is a fantasy. While investors can ...