\begin{table}%t5
\caption{Number of detected maser galaxies per luminosity and distance interval (see Table~\ref{t4})$^{a}$.}\label{t5}
%\centerline
 {\begin{tabular}{ccccccc}
\hline\hline
log~($L_{\rm H_2O}$) & \multicolumn{6}{c}{Distance}                                \\
($L_{\odot}$)         & \multicolumn{6}{c}{(Mpc)}                                   \\
\hline
                     & $<$2   &   2--6   &  6--21    & 21--65 & 65--210 & 210--650  \\
\hline
--1.0--(--0.1)        &    2   & {\it 1}  &     2     &   --   &   --    &    --     \\
0.0--0.9             &   --   &    1     &  {\it 4}  &   --   &   --    &    --     \\
1.0--1.9             &   --   &    2     &     2     &{\it 12}&    4    &    --     \\
2.0--2.9             &   --   &   --     &     4     &    7   & {\it 7} &    --     \\
3.0--3.9             &   --   &   --     &    --     &   --   &    3    & {\it 1}   \\
\hline
\end{tabular}}
\medskip
$^a$ In italics: expected highest distance bin where sources of a given luminosity should still
be detectable. Because this 
distance bin contains a much larger volume than the nearer ones, most masers are expected to be there. For each of the galaxies 
in Table~\ref{t4} the total integrated 22~GHz H$_2$O luminosity was taken. This amounts to an  integrated single-dish flux density 
corresponding to $\sim$8~$L_{\odot}$ in the case of NGC~2146, where VLA data from Tarchi et~al. (\cite{Tar02b}b) revealed two 
$\sim$1~$L_{\odot}$ masers (see Table~\ref{t4}). 
\end{table}