\begin{table}%t6
\caption{Values of $\beta$ calculated from the damping timescales in Tables~\ref{table2a} and~\ref{table2b}.}\label{table5}
%\centering
\small
\begin{tabular}{@{\extracolsep{\fill}}c c c}
\hline \hline
$L$~(cm)&Equilibrium&Non-equilibrium\\
\hline
&&  \\[-8pt]
$2\times10^9$&--0.51~($R^2=0.8205$)&--0.56~($R^2=0.7886$)\\
$4\times10^9$&--0.39~($R^2=0.9966$)&--0.33~($R^2=0.9979$)\\
$8\times10^9$&--0.21~($R^2=0.8317$)&--0.19~($R^2=0.8145$)\\
$16\times10^9$&--0.08~($R^2=0.3940$)&--0.07~($R^2=0.3239$)\\
\hline
\end{tabular}
\end{table}