\begin{table}
\begin{center}
\caption[]{\label{cham_table5} Mean space velocities and dispersions
separately for stars of subgroups~1 \& 2 and Hipparcos PMS stars as well
as for the total samples, as shown in Fig.~\ref{cham_uvw}.
$U$-velocities are positive in the direction of the galactic centre.
The velocities have been corrected for the effects of differential 
galactic rotation and the reflex motion of the Sun.
For the calculation of the space velocities we used either the Hipparcos
parallaxes or, where not available, a distance of 170\,pc for stars in
subgroup~1 and 90\,pc for stars in subgroup~2.}
\bigskip
\hspace*{-0.5cm}
\begin{tabular}{l@{$\qquad$}r@{$\qquad$}cr@{$\qquad$}cr@{$\qquad$}cr}
\hline\noalign{\smallskip}
& & \multicolumn{1}{c}{$<U>$} & \multicolumn{1}{c}{$\sigma_{U}$} & 
\multicolumn{1}{c}{$<V>$} & \multicolumn{1}{c}{$\sigma_{V}$} &
\multicolumn{1}{c}{$<W>$} & \multicolumn{1}{c}{$\sigma_{W}$} \\
 & \raisebox{1.5ex}[-1.5ex]{\#}& 
\multicolumn{2}{c}{[km/s]} & \multicolumn{2}{c}{[km\,s$^{-1}$]} &
\multicolumn{2}{c}{[km/s]} \\
\noalign{\smallskip}\hline\noalign{\smallskip}
subgroup 1            &  4 & \hphantom{-1}4.8 & 6.5 & -10.8 & 8.2 & -3.5 & 2.6 \\
subgroup 2            &  7 & \hphantom{-1}2.8 & 3.0 & \hphantom{1}-7.8 & 3.2 & -2.5 & 1.5 \\
subgroups 1 \& 2      & 11 & \hphantom{-1}3.5 & 4.4 & \hphantom{1}-8.9 & 5.4 & -2.9 & 2.0 \\
Hipparcos PMS         &  6 & \hphantom{-1}5.2 & 5.5 & \hphantom{1}-9.6 & 6.7 & -3.1 & 2.5 \\
all Hipparcos stars   & 11 & -14.9 & 30.6 & -10.7 & 18.5 & -1.1 & 11.9 \\
\noalign{\smallskip}\hline\\[0.8ex]
\end{tabular}
\end{center}
\end{table}
