How concentrated is the MSCI Emerging Markets Index? Its top 10 constituents represent about 39% of the index, near a 20-year high and up from roughly 15%. That is a similar share to the top 10 of the MSCI USA Index, even though the emerging markets index held more than twice as many constituents (1,205 vs. 536). Taiwan Semiconductor Manufacturing alone represented about 14.5%, more than the combined weight of the constituents of the MSCI India Index.