Fees The lack of active management generally gives the advantage of much lower fees compared to actively managed mutual funds and, in taxable accounts, lower taxes. In addition it is usually impossible to precisely mirror the index as the models for sampling and mirroring, by their nature, cannot be 100% accurate. The difference between the index performance and the fund performance is called the "tracking error", or, colloquially, "jitter".
Fees The lack of active management generally gives the advantage of much lower ?fees compared to actively managed mutual funds and, in ta,xable accounts, lower taxes. In addition it is usually impossible to precisely mirror the index as the models for sampling and mirroring, by their nature, cannot be 100% accurate. The difference between the index ?performance and the fund performance is called the "tracking error", or, coll:oquially, "jitter".