\begin{table}%t2
\caption{\label{tab:rgi}Summary of $r_{\rm GI}$ for different values of $z_i$ and the three survey models.}
%%\centering

\par
\begin{tabular}{ccccccc}
\hline\hline\noalign{\smallskip}
Survey & $z_i$ & $\sigma_{\rm opt}$ &$r_{\rm GI}$(auto) & $r_{\rm GI}$(mid) & $r_{\rm GI}$(far) & $r_{\rm GI}$(boost)\\
\hline 
S  & 0.53 & 0.055 & 0.04 & 0.47 & 0.56 & 78.26\\
   & 0.76 & 0.085 & 0.02 & 0.25 & 0.32 & 415.79\\
   & 0.96 & 0.095 & 0.01 & 0.16 & 0.22 & 62.10\\
P1 & 0.53 & 0.055 & 0.12 & 0.46 & 0.54 & 13.56\\
   & 0.76 & 0.085 & 0.06 & 0.24 & 0.31 & 20.49\\
   & 0.96 & 0.095 & 0.04 & 0.16 & 0.21 & 25.86\\
P2 & 0.52 & 0.045 & 0.19 & 0.47 & 0.55 & 5.97\\
   & 0.74 & 0.050 & 0.10 & 0.26 & 0.32 & 7.75\\
   & 0.98 & 0.055 & 0.06 & 0.15 & 0.20 & 11.63\\
\hline
\end{tabular}
\tablefoot{Given are values of $r_{\rm GI}$ of the original power spectra for the auto-correlation (``auto''), the cross-correlation between bin $i$ and the background bin with index $(i+N_z)/2$ (``mid''), and the cross-correlation between bin $i$ and the most distant bin with index $N_z$ at $z \lesssim 2$ (``far''). The tag ``boost'' stands for the transformed signals. In addition $\sigma_{\rm opt}$ is listed for every considered case.}
\end{table}