Calculate daily S&P$500$ index returns and daily cumulative returns over the sample period $($ Dec $28,2023$ to december $52023)$:

$3)$ Compute daily cumulative returns:

$4)$ Calculate the mean and standard deviation of daily returns.

$5)$ Plot the cumulative returns over the sample period $($X$-$axis: Date, Y$-$axis: Cumulative Return$).$

$6)$ Explain the plot by identifying trends, significant events, or periods of high volatility.