\begin{table}%t9
%\centering
\par
\caption{Global VLBI array rms astrometric errors (in $\mu$as) for a relative source separation
$(\alpha -\alpha _0)\cos\delta_0 = 1\degr$. The individual astrometric error contribution from wet troposphere
uncertainties is given separately along with the total astrometric errors when all
model parameters are perturbed together.
\label{GlobalRA}}
\small 
\begin{tabular}{lcccccccccccccccccc}
\hline\hline
\noalign {\vskip 1.0mm}
&&\multicolumn{16}{c}{Declination of source}\\
\noalign {\vskip 0.5mm}   \noalign {\vskip 1.0mm} \hfil
\hfil
&&\multicolumn{2}{c}{$-25\degr$}&&\multicolumn{2}{c}{$0\degr$}&&\multicolumn{2}{c}{$25\degr$}
        &&\multicolumn{2}{c}{$50\degr$}&&\multicolumn{2}{c}{$75\degr$}&&\multicolumn{2}{c}{$85\degr$}\\
\noalign {\vskip 0.0mm}
Error component &&$\Delta\alpha\cos\delta \hfil$ &$\Delta\delta$ &&$\Delta\alpha\cos\delta \hfil$ &$\Delta\delta$&&
        $\Delta\alpha\cos\delta \hfil$&$\Delta\delta$&&$\Delta\alpha\cos\delta \hfil$&$\Delta\delta$&&
        $\Delta\alpha\cos\delta \hfil$&$\Delta\delta$&&$\Delta\alpha\cos\delta \hfil$&$\Delta\delta$\\
\noalign {\vskip 0.0mm}
\hline
Wet troposphere (mean)   &&   71  &   76   &&   32   &   42 && 26   &   34  &&   23  &   13  &&   22  &   ~6 && ~27 & ~~9 \\
Total (mean wtrp)       &&   82  &   67   &&   34   &   46 && 24   &   44  &&   34  &   33  &&   64  &   76 && 196 & 203\\
\hline
\end{tabular}
\end{table}