\begin{table}%tB.1
%\centering
\par
\caption{Mean offset, rms ($\sigma$), and rms expected by 
the errors ($\sigma$(exp)) in the comparison between stars observed
in Run~4 and in the other runs. The last column shows the $z$ parameter,
which indicates the significance of the mean offset. A $z$-value higher 
than 1.96 indicates that the offsets are significant with a significance 
level lower than 0.05.\label{tab.dc}}
\small
\begin{tabular}{l rrrrr}
\hline\hline
Index       & Offset &  $\sigma$ & $\sigma$(exp)  & $z$ \\
\hline
H$\delta_A$ &$-0.141$&  0.249    & 0.117          & 1.18\\
H$\delta_F$ &$-0.021$&  0.135    & 0.092          & 0.38\\
%CN$_1$      &$-0.012$&  0.010    & 0.006          & 1.74\\
CN$_2$      &$-0.004$&  0.016    & 0.006          & 0.56\\
Ca4227      &$ 0.095$&  0.279    & 0.045          & 0.78\\
G4300       &$-0.017$&  0.524    & 0.087          & 0.08\\
H$\gamma_A$ &$-0.235$&  0.680    & 0.151          & 0.79\\
H$\gamma_F$ &$ 0.017$&  0.282    & 0.107          & 0.15\\
Fe4383      &$ 0.129$&  0.362    & 0.201          & 0.81\\
Ca4455      &$ 0.219$&  0.329    & 0.066          & 1.32\\
Fe4531      &$ 0.099$&  0.146    & 0.097          & 1.34\\
C4668       &$-0.010$&  0.200    & 0.310          & 0.12\\
H$\beta$    &$-0.045$&  0.091    & 0.063          & 1.06\\
Fe5015      &$ 0.004$&  0.137    & 0.149          & 0.07\\
Mgb         &$ 0.077$&  0.079    & 0.067          & 1.64\\
\hline
\end{tabular}
\end{table}