\begin{table}%t2
\caption{\label{frac}Percentage of polarized sources at {\it low resolution}.}
%\centering
\par
\begin{tabular}{rrrr}
\hline\hline
8.5~GHz &    4.9~GHz &   1.4~GHz &~$m_{\rm v}/\sigma_{m_{\rm v}}$ \\
\hline
       73\%   &	65\%   &   58\%    &   ~$\ge$2~~~~~~\\
\par
       64\%   &	58\%   &   47\%    &   ~$\ge$3~~~~~~\\
\par
       51\%   &	42\%   &   32\%    &   ~$\ge$5~~~~~~\\
\hline
\end{tabular}
\end{table}