RT Journal Article SR Electronic T1 Editor’s Letter JF The Journal of Index Investing FD Institutional Investor Journals SP 1 OP 2 DO 10.3905/jii.2021.12.2.001 VO 12 IS 2 A1 Bruce, Brian YR 2021 UL http://jii.pm-research.com/content/12/2/1.abstract AB