Do Bonds Reduce the Overall Risk of an Investment Portfolio $$\sum x$$

Multiple Choice

Do bonds reduce the overall risk of an investment portfolio? Let x be a random variable representing annual percent return for the Vanguard Total Stock Index (all Stocks) . Let y be a random variable representing annual return for the Vanguard Balanced Index (60% stock and 40% bond) . For the past several years, assume the following data. Compute. $$\sum x$$ $$\begin{array} { l l l l l l l l l l l } x : & 14 & 0 & 36 & 24 & 31 & 26 & 27 & - 14 & - 14 & - 24 \\y : & 8 & - 1 & 26 & 17 & 25 & 18 & 17 & - 1 & - 2 & - 8\end{array}$$

A) 134
B) 106
C) 154
D) 75
E) 130