\begin{table}%t3
\caption{Parameters derived from the model of Faraday depolarization
and their $2\sigma$ errors.}\label{tab:dp}
%\centering
\par
\begin{tabular}{llll} 
\hline  \hline
  Ring (kpc) & $q=h\syn/h\therm$ & $DP_{{\rm in}}$ & $h\therm$ (kpc)  \\
  \hline 
  6--8 & \multicolumn{3}{c}{No statistically good fit found}  \\
  8--10 & $0.6\pm 0.1$ & $0.1\pm 0.1$ & $0.55\pm0.10$ \\
  10--12 & $\rm 0.4^{+0.4}_{-0.2}$ & $\rm 0.3^{+0.7}_{-0.1}$ & $\rm 0.90^{+0.90}_{-0.45}$ \\
  12--14 & $\rm 0.3^{+0.5}_{-0.3}$ & $0.2\pm 0.2$ & $\rm 1.3^{+2.6}_{-0.8}$ \\
  \hline 
\end{tabular}
\end{table}