\begin{table}%t6
\caption{Distribution parameters and their uncertainties
from a \protect 9-parametric Gaussian model applied to M~67~cluster and the field.
$n_{\rm c}$ measures the volume of the cluster frequency function 
($n_{\rm f} = 1- n_{\rm c}$), $\mu_x$ and~$\mu_y$ are the mean relative proper motions, $\sigma_{\rm c}$, and~$\sigma_{\mu_x}$ and~$\sigma_{\mu_y}$ are the dispersions of the
Gaussians fitted to the cluster and field distributions,
and~$\rho$ is the correlation for the field function (it fixes the 
orientation of the field elliptical function). The units of~$\mu$ and~$\sigma$ are mas~yr$^{-1}$.}\label{para67}
%\centering
\small      
\begin{tabular}{lc c c c c c c }
\hline \hline
& $n_{\rm c}$
& $ \mu_{x}$ &
$\mu_{y}$ & 
$\sigma_{\rm c}$  &
$\sigma_{\mu_{x}}$ & $\sigma_{\mu_{y}}$ 
& $\rho$\\
\hline
M~67& 0.364 & $-$0.59 & 0.49 & 0.89 &  &  &  \\
& $\pm0.016$ & $\pm0.07$ & $\pm0.06$ & $\pm0.05$  &  &  &  \\
Field  &
& 0.02 & 3.31  &  &9.00 & 8.63 & $-0.21$\\
&   & $\pm0.10$ & $\pm0.48$ & &$\pm0.03$ & $\pm0.24$ & $\pm$0.02 \\
\hline
\end{tabular}
\end{table}