\begin{table}%t3
%\centering
\par
\caption{\label{t:ratios}Median column density ratios and ratio ranges of  different molecules with respect to \OHP\ \citep{menten+2010,polehampton+2005,vastel+2002}.}
\begin{tabular}{lrrr}
\hline\hline 
\noalign{\smallskip}
& \multicolumn{3}{c}{$N$(X)/$N$(\OHP)} \\
\cline{2-4}
\noalign{\smallskip}
 Molecule & Min. & Median & Max. \\ 
\hline 
SH$^+$ &       0.03 &       0.13 &       1.28 \\
CH$^+$ &       0.13 &       0.43 &       2.61 \\
OH &      10.50 &      15.83 &     245.09 \\
\OI\ &    1191.42 &    2587.08 &   11392.25 \\
\hline
\end{tabular}\vspace*{-1.5mm}
\end{table}