\begin{table}%T6
\caption{\label{tab6}Best fitting parameters for each dataset.}
%\centering
\par
\begin{tabular}{ccccccc}
\hline 
\hline
Error  & \multicolumn{2}{c}{$D_{\rm V}$} & &
\multicolumn{2}{c}{$\log(M_{\rm V})$}  & ~$t_0$  \\
       & \multicolumn{2}{c}{(Mpc)}   & & 
\multicolumn{2}{c}{($M_{\odot}$)}            &   (Gyr)        \\  
\cline{2-3}
\cline{5-6}
       &   mean &~$\sigma$  & &  mean & ~$\sigma$  &  \\ \hline
~~0\% & 16.7   & 0.5  &  &  14.5 &   0.2 &  14.1\\
~~5\% & 16.8   & 0.5  &  &  14.6 &   0.3 &  13.9\\
10\%   & 16.9   & 0.6  &  &  14.9 &   0.4 &  12.8\\
15\%   & 17.0   & 0.8  &  &  15.1 &   0.5 &  12.1\\
20\%   & 17.1   & 0.9  &  &  15.5 &   0.5 &  10.1 \\
25\%   & 17.1   & 1.0  &  &  15.7 &   0.4 &  ~~9.0 \\
30\%   & 17.1   & 1.0  &  &  16.1 &   0.5 &  ~~6.7  \\
\hline
\end{tabular}
\end{table}