This first move is a small one, relatively: A shares account for less than half of 1 percent of the MSCI Emerging Markets index. Index funds that track the MSCI Emerging Markets index bought A shares so they can track the performance of the newly constituted index. Actively managed emerging-market funds aren't required to buy A shares, but they will now have to compare their performance against the MSCI Emerging Markets index, which does have them. The A share market is one the world's largest and has more than 3,000 stocks. Because they make up just 0.4 percent of the Emerging Markets index, their swings likely won't bring noticeable day-to-day effects for funds.

Source: ABC News June 07, 2018 18:00 UTC