\begin{table}%t3 \caption{\label{resum}Distribution parameters for HIPPARCOS and GCS~samples with radial velocity errors up to 2.5~km~s$^{-1}$ (Samples~I', II', III', and~IV')\tablefootmark{\dag}.} \par %\centering \par \begin{tabular}{rcccccccccccccccc} \hline \hline\noalign{\smallskip} Sample & $\sigma_{U}$&$\sigma_{V}$&$\sigma_{W}$ & $\delta~[^\circ]$ &$c_U$ &$c_V$ &$c_W$ &$\gamma_U$ &$\gamma_V$ &$\gamma_W$ \\\hline HIP total &36.2 $\pm$ 0.6&30.8 $\pm$ 1.0& 18.6 $\pm$ 0.5&7.6 $\pm$ 6.6&9.3 $\pm$ 4.0 &37.0 $\pm$ 13.9 &20.7 $\pm$ 14.8 &0.2 $\pm$ 0.2 &--4.5 $\pm$ 0.8 &--0.9 $\pm$ 0.5 \\ $|{\bf V}|\leq 51$&19.9 $\pm$ 0.1&13.2 $\pm$ 0.1& 10.7 $\pm$ 0.1 &12.3 $\pm$ 0.8 &--0.4 $\pm$ 0.1 &0.1 $\pm$ 0.3 &1.5 $\pm$ 0.5 &0.3 $\pm$ 0.0 &0.2 $\pm$ 0.0 &0.2 $\pm$ 0.1 \\\hline GCS total&35.2 $\pm$ 0.4& 26.1 $\pm$ 0.6& 18.6 $\pm$ 0.5 &10.7 $\pm$ 2.4 &5.5 $\pm$ 2.8 &22.7 $\pm$ 9.3 &35.2 $\pm$ 42.4 &--0.1 $\pm$ 0.2 &--3.1 $\pm$ 0.5 &--0.9 $\pm$ 1.0 \\ $|{\bf V}|\leq 51$&21.5 $\pm$ 0.1& 14.1 $\pm$ 0.1& 12.4 $\pm$ 0.1 &8.7 $\pm$ 0.6 &--0.7 $\pm$ 0.1 &0.0 $\pm$ 0.2 &0.7 $\pm$ 0.3 &0.2 $\pm$ 0.0 &0.2 $\pm$ 0.0 &0.1 $\pm$ 0.0 \\ \hline $e\leq 0.3$&29.1 $\pm$ 0.2 & 18.1 $\pm$ 0.1 & 11.6 $\pm$ 0.1 &9.6 $\pm$ 0.6 &0.2 $\pm$ 0.2 &0.4 $\pm$ 0.2 &--0.4 $\pm$ 0.1 &0.1 $\pm$ 0.0 &--0.3 $\pm$ 0.0 &0.0 $\pm$ 0.0 \\ \hline \end{tabular} \tablefoot {\tablefoottext{\dag}{The last sample contains representative thin disc stars, obtained from eccentricities $e\leq 0.3$ and $|z_{\rm max}|\leq 0.5$~kpc. The displayed parameters are dispersions~$\sigma_{U}$, $\sigma_{V}$, $\sigma_{W}$, vertex deviation~$\delta$ on the $UV$-plane, curtosis~$c_U$, $c_V$, $c_W$, and skewness~$\gamma_U$, $\gamma_V$, $\gamma_W$.}} \end{table}