$($Calculating rates of return$)$ The S&P stock index represents a portfolio comprised of $500$ large publicly traded companies. On December $24,2007,$ the index had a value of $1,410$ and on December $24,2008,$ the index was approximately $904.$ If the average dividend paid on the stocks in the index is approximately $4\mathrm{.}5$ percent of the value of the index at the beginning of the year, what is the rate of return earned on the S&P index? What is your assessment of the relative riskiness of investing in a single stock such as Google compared to investing in the S&P index $?$