\begin{tabular}{|l|l|l|} \hline Overall, the 30-year rates are & \multicolumn{2}{|l|}{ the 15-year rates. } \\ \hline The variability is & & \\ \hline Average of the differences = & & \\ \hline \end{tabular} and the 15-year rates. Also, calculate the average of the differences between the rates. (Input the amount as positive value. Round your answer to 4 decimal places.)