\begin{table}%t6
\par
\caption{\label{t6} Differences of differential magnitude and colours over two years (1999--2001).}
%\centerline
{\begin{tabular}{rrrrrrrrr}
\noalign{\smallskip}
\hline\hline
\noalign{\smallskip}
HIP &  $\delta\Delta V$ & $\sigma(\delta\Delta V$) & $\delta(\Delta B-\Delta V$) & $\sigma(\delta(\Delta B-\Delta V$))
    & $\delta(\Delta V-\Delta R$) & $\sigma(\delta(\Delta V-\Delta R$)) & $\delta(\Delta V-\Delta I$) & $\sigma(\delta(\Delta V-\Delta I$)) \\
\hline                                                                                
2552   &  0.011 & 0.006 &  0.010 & 0.013 &  0.000 & 0.008 &  0.037 & 0.008 \\
86282  & --0.004 & 0.002 & --0.011 & 0.004 & --0.042 & 0.026 & --0.024 & 0.004 \\
110893 &  0.011 & 0.015 &  --    & --    &  0.001 & 0.032 &  0.055 & 0.046 \\
\hline
\end{tabular}}
\end{table}