There are many index tracking ETFs but the two organisation that manage and track index that almost all ETFs adhere to are MSCI and S&P. you can find out more information here Index Solutions - MSCI
Every Quarter and six months these organisation published what stocks should be in what index and all index tracking ETFs out there that track this index has to buy and sell according to this list, don't know how many out there but there certainly be a few, Blackrock is one there iShares, Xtrackers etc...
MFG is part of MSCI global index composition you can look at it here where it got dumped with the latest rebalance MSCI_Feb22_STPublicList.pdf
the ASX50, 100 and 200 is probably based on S&P and when they published their rebalance list that when it matters
A personalised tool to help users track selected stocks. Delivering real-time notifications on price updates, announcements, and performance stats on each to help make informed investment decisions.
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