\begin{table} %T4
\caption{\label{tab: eff}Best-fit EFF87 parameters for different populations in Tr~14. }
\small%\centering
\par
\begin{tabular}{ccccccc}
\hline
\hline\noalign{\smallskip}
     Population & $K_{\rm S}$ range& $\Sigma_0$ [pc$^{-2}$]   &       $a$ [pc]      &    $\gamma$ &  $r_{\rm c}$ [pc] &  $n_0$ [pc$^{-3}$] \\
\hline 
\multicolumn{6}{c}{Without colour selection}\\ 
\vspace*{1mm}  MS~&  6--12 &     1077 $\pm$      567 & 0.05 $\pm$ 0.03     & 1.66 $\pm$ 0.27     & $0.06_{\rm -0.03}^{+0.03}$     &   $  9871_{\rm -6376}^{+10497}$  \\
\vspace*{1mm} PMS~& 12--18 &    10330 $\pm$      770 & 0.13 $\pm$ 0.01     & 2.17 $\pm$ 0.08     & $0.11_{\rm -0.01}^{+0.01}$     &   $ 40~715_{\rm -4520}^{+5019}$  \\
\vspace*{1mm} All &  6--18 &    11116 $\pm$      817 & 0.13 $\pm$ 0.01     & 2.18 $\pm$ 0.08     & $0.11_{\rm -0.01}^{+0.01}$     &   $ 44~665_{\rm -4864}^{+5390}$  \\ 
\multicolumn{6}{c}{With colour selection}\\ 
\vspace*{1mm}  MS~&  6--12 &   3097 $\pm$ 14013 & 0.01 $\pm$ 0.03 & 1.25 $\pm$ 0.39 & $0.01_{\rm -0.05}^{+0.05}$  &    \dots  \\
\vspace*{1mm} PMS~& 12--18 &   3977 $\pm$   289 & 0.32 $\pm$ 0.04 & 3.26 $\pm$ 0.19 & $0.23_{\rm -0.03}^{+0.03}$  &    $8348_{\rm -1070}^{+1258}$ \\
\vspace*{1mm} All &  6--18 &   4321 $\pm$   316 & 0.30 $\pm$ 0.03 & 3.10 $\pm$ 0.17 & $0.22_{\rm -0.03}^{+0.03}$  &    $9491_{\rm -1199}^{+1394}$ \\
\hline
\end{tabular} 
\tablefoot{The uncertainties on $\Sigma_0$, $a$ and $\gamma$ are the 1\s\ error bars.
The uncertainties on $r_{\rm c}$ and  $n_0$ were computed using Monte Carlo simulations assuming a Gaussian distribution of the errors on $\Sigma_0$, $a$ and $\gamma$. The quoted values give the 0.68 confidence interval.}
\end{table}