Although index funds have been around for over 50 years, their initial acceptance was slow. After being available for 25 years, they represented less than 5% of all investments in US equities, with the Australian experience being similar. In the late 1990s, the acceptance of index investing began to take off and by the early 2020s, it represented in excess of 50% of all US equity investment. Initially, index funds were only available on the major indexes (e.g., S&P500, ASX200). However, growth of index investing saw the proliferation of indexes...