From the end of 1990 to the end of 2008, the Standard & Poor’s 500 (S&P 500) U.S. stock index rose from 330.2 to 903.3. If you had invested US$50,000 at the end of 1990 in a portfolio of the shares of the 500 companies in the Index, what would the value (in US$) of those shares have been at the end of 2008? (This calculation considers only the price appreciation of the original shares. It does not include additional growth in the portfolio’s value resulting from the receipt and reinvestment of dividends.)