Emerging markets index relies on few equities

The MSCI Emerging Markets index has a heavy weight on Asia. China has the largest weighting at more than 31%, followed by Taiwan, India and South Korea. The five biggest countries total nearly 77%.

The countries' indexes have heavy concentrations in a small number of equities, with the 10 largest stocks having 39% to 61% weights. For instance, Taiwan Semiconductor Manufacturing Co. makes up more than 42% of the MSCI Taiwan index.

Among the five countries, Taiwan had the highest 10-year return and lowest volatility for the period ended April 28. The index had an annualized 10.1% return, with Taiwan Semiconductor producing a 21% return. At the other end of the spectrum, Brazil's return was -1.8%, and the 34.7% volatility was the highest.