\begin{table}%t2
\caption{\label{counterparts}Number of objects with a USNO-B and UCAC2 counterpart.}
\small%\centerline
 {
\begin{tabular}{lcccc}
\hline\hline
Survey                         & Number of     & Total USNO-B & USNO-B counterparts  & UCAC2          \\
                               & objects       & counterparts & with proper motion   & counterparts   \\
\hline                                                                       
\citet{2002AJ....124..404P}    & 166           & 166          & 123                  & 87            \\
\citet{2000AJ....120..479A}    & 20            & 20           & 12                   & 1             \\
\citet{2004AJ....127..449M}    & 28            & 23           & 14                   & 0             \\
\citet{Martin_inprep}          & 7             & 6            & 3                    & 0             \\
\citet{2008ApJ...688..377S}    & 127           & 121          & 93                   & 2             \\
\hline 
Total                          & 515           & 476          & 227                  & 90             \\
\hline
\end{tabular}}
\medskip
Note. All UCAC2 sources have a proper motion measurement.
\end{table}