19.9 During the 1980s and 1990s, changes in the S&P 500 were about 50% correlated with the MSCI EAFE (Europe, Australasia, Far East) Index. In recent years, the correlation has increased to more than 90%. Why? If an analyst wishes to calculate the cost of equity, which index should he or she use in estimating the equity risk premium? (Appendix)