\begin{table}%t2
\caption{Damping timescales of the fundamental mode standing wave for an equilibrium ionisation balance. The associated percentage errors are quoted in brackets.}\label{table2a}
%\centering
\small
\begin{tabular}{@{\extracolsep{\fill}}c c c c c c c}
\hline \hline
&0.5~(MK)&1.0&2.0&4.0&8.0\\
\hline
&&&&& \\[-8pt]
$2\times10^9$~cm&321(8\%)~s&169(16\%)&158(15\%)&...&...\\
$4\times10^9$&753(11\%)&592(6\%)&441(4\%)&...&...\\
$8\times10^9$&1071(4\%)&1053(4\%)&926(4\%)&847(12\%)&570(10\%)\\
$16\times10^9$&1424(0\%)&1616(1\%)&1593(2\%)&1438(14\%)&1161(10\%)\\
\hline
\end{tabular}
\end{table}