\begin{table}%t1
      \caption{\label{tab1}Percentage of clusters with substructure.}
%\centering
\small
         \begin{tabular}{cccc}
            \hline\hline
            Radius &  $M_{r}<-20$ & $M_{r}<-19$ & No mag. limit\\
            \hline
           $r<r_{200}$ & 11& 33 & 34\\
           $r_{200}<r<2r_{200}$ & 55& 57 &44\\
            \hline
         \end{tabular} 
   \end{table}