\begin{table}%t7
\caption{\label{dindex}Inferred metallicity, $N_{\rm HI}$ and $D$-index of Mg~{\sc ii} systems with $W_{\rm r}>1.0$~\AA ~ in the UVES sample.}
%\centerline
{
\begin{tabular}{l c c c c}
\hline\hline\noalign{\smallskip}
GRB & $z_{\rm abs}$   &   [X/H]$^a$ & $N_{\rm HI}({\rm cm}^{-2})^a$ &$D$-index$^b$\\
\hline
021004& 1.380   &$-0.63$& 20.3&$8.32\pm0.22$ \\[0.5ex]
021004& 1.603  &$-0.65$&20.8& $9.99\pm0.47$ \\[0.5ex]
050820A& 0.692  &      & &$9.0\pm0.03^c$  \\[0.5ex]
050820A& 1.429  &$-0.34$&  $>$$19.2$ &$8.13\pm0.22$ \\[0.5ex]
060418& 0.603  &$-1.13$&   $>$$22.0$&$10.39\pm0.09^d$ \\[0.5ex]
060418& 0.656    &$-0.77$&$>$$19.2$ &$7.51\pm0.05$\\[0.5ex]
060418& 1.107  &$-0.85$&21.1 &$8.17\pm0.06$ \\[0.5ex]
060607A& 1.803  &$-0.21$& 19.0&$9.12\pm0.06$ \\[0.5ex]
080319B& 0.715  &$-0.17$& $>$$18.7$&$8.06\pm0.01$ \\[0.5ex]
 \hline
\end{tabular}}
\par
\medskip
$^a$ Metallicities and  $N_{\rm HI}$ values inferred using the relation by \cite{Ledoux2006a}; 
$^b$ {\it D}-index calculated using Eq.~\ref{eqd}, following the method recommended by \cite{Ellison2009};
$^c$  {\it D}-index calculated without including the iron column density term (see \citealt{Ellison2009});
$^d$ iron lines are saturated. The {\it D}-index calculated without including the iron column density term would be $D=9.48\pm0.08$;
\end{table}