\begin{table}%t7
\caption{The percentage of objects with steep spectra ($\alpha_{\rm r}>0.5$;
 $S_{\nu}\propto\nu^{-\alpha_{\rm r}}$) is listed for different datasets.}
\label{perc. steep spectra}
%%\centering
\par
\begin{tabular}{lrccc}
\hline  \hline
\multicolumn{2}{c}{Datasets} & \% & $\Delta$ & VLA \\
20 cm & 6 cm & steep sp. & yrs & config. \\
\hline  
CWSR & CWSR & 15.4 & 0 &C+C/D$^*$\\
\hline
NVSS & EMSS & 38.5 & 5--10 &D, C\\
NVSS & CWSR & 38.5 & 4--7 &D, C\\
CWSR & EMSS & 23.1 & 12--14 &C+C/D, C\\
\hline 
\multicolumn{5}{l}{$^*$ Also 3.6 cm observations in C configuration and 18 and 2 cm observations} \\
\multicolumn{5}{l}{in C/D configuration are used.} \\
\end{tabular}
\end{table}