\begin{table}%t3
  \caption{\label{tb3}Surplus angular rates of rotation produced by the subset
 of Hipparcos proper motions of Case 3 based on the standard value of the
 Oort constant, $Q=-2.53$~mas/yr, and its variations for comparison (errors
 are only given for the standard value of $Q$ as those of the comparative
 cases are almost identical). }
%\centerline
{
 \begin{tabular}{cccc}   
   \hline \hline  
        $Q$       & $\Delta\omega_x$ & $\Delta\omega_y$ &  $\Delta\omega_z$ \\ 
           \  [mas/yr]   &   [mas/yr]       &   [mas/yr]      &   [mas/yr]       \\ 
   \hline   
          $-2.0 $  & 0.52           & 0.22           & $-0.95$       \\
          $-2.2 $  & 0.35           & 0.18           & $-0.86$       \\
          $-2.4 $  & 0.17           & 0.14           & $-0.77$       \\  
          $-2.53^{\star}$ & 0.06  & 0.12           & $-0.71$       \\[-1.4mm]
            ~       & $\pm$$0.52$  & $\pm$$0.12$  & $\pm$$0.28$  \\  
          $-2.8  $  & $-0.18$    & 0.07           & $-0.59$       \\
          $-3.0  $  & $-0.35$    & 0.03           & $-0.50$       \\   
   \hline
   \end{tabular}   }
   \smallskip
   $^{\star}$~ Kerr \& Lynden-Bell (\cite{klyb1986}).
\end{table}