Can somebody help me figure this out please? I don't get how to calculate returns in general.

KELLOGG annual stock prices \begin{tabular}{|c|r|r|} \hline Date & Adjusted closing price & Return \\ \hline 1/Dec/95 & 22.4 & \\ \hline 2/Dec/96 & 19.46 \\ \hline 1/Dec/97 & 30.08 \\ \hline 1/Dec/98 & 21.21 \\ \hline 1/Dec/99 & 19.67 \\ \hline 1/Dec/00 & 17.43 \\ \hline 3/Dec/01 & 20.71 \\ \hline 2/Dec/02 & 24.28 \\ \hline 1/Dec/03 & 27.82 \\ \hline 1/Dec/04 & 33.42 \\ \hline 1/Dec/05 & 33.11 \\ \hline 1/Dec/06 & 39.27 \\ \hline 3/Dec/07 & 42.08 \\ \hline 1/Dec/08 & 36.13 \\ \hline 1/Dec/09 & 45.25 \\ \hline 1/Dec/10 & 44.8 \\ \hline 1/Dec/11 & 45.78 \\ \hline 3/Dec/12 & 52.26 \\ \hline 2/Dec/13 & 58.85 \\ \hline 1/Dec/14 & 64.94 \\ \hline \end{tabular} You have data on annual stock prices for Kellogg for 1995-2014. - Compute the average annual return and the standard deviation of annual returns for Kellogg. Average annual return Std. Deviation