PT - JOURNAL ARTICLE AU - Brian Bruce TI - Editor’s Letter AID - 10.3905/jii.2021.12.1.001 DP - 2021 May 31 TA - The Journal of Index Investing PG - 1 VI - 11-12 IP - 4-1 4099 - https://pm-research.com/content/11-12/4-1/1.short 4100 - https://pm-research.com/content/11-12/4-1/1.full