\begin{table}%t0
%\centering
\small
\begin{tabular}{cccccccccrr}
\hline\hline
& \multicolumn{10}{c}{$\tau_{\rm o}$} \\
\hline
"old'' & 1.0 & 2.0 & 3.0 & 4.0 & 5.0 & 6.0 & 7.0 & 8.0 & 9.0  & 10.0 \\
"new'' & 1.3 & 2.6 & 3.8 & 4.9 & 6.0 & 7.0 & 8.1 & 9.1 & 10.2 & 11.0 \\
\hline
\end{tabular}                                
\end{table}