\begin{table}%t2
%\begin{center}
\par
\caption{North-South, East-West and polarity asymmetry in the number of structures (\%) 
for various selections in term of size, polarity and hemisphere (defined as the 
difference in numbers $N$ of structures -- first criterion minus the second one -- 
divided by their sum). The uncertainties correspond to 1/$\sqrt{N}$. The area $A$ is in Mm$^2$.} 
\label{tabnb_pourcent}
\begin{tabular}{ccc}
\hline \hline
Selection & 25 G (\%) & 40 G (\%) \\ \hline
$North$, $S\!outh$ & $-0.43\pm0.05$ & $0.98\pm0.07$ \\
$North$, $S\!outh$ ($A>800$) & $2.07\pm0.52$ & $0.61\pm0.61$ \\
$North$, $S\!outh$ ($40<A<800$) & $2.07\pm0.10$ & $3.03\pm0.13$ \\
$North$, $S\!outh$ ($A<40$) & $-1.48\pm0.06$ & $0.15\pm0.08$ \\ \hline
$B>0$, $B<0$& $-2.96\pm0.05$ & $-0.61\pm0.07$ \\
$B>0$, $B<0$ ($A>800$) & $-0.95\pm0.53$ & $0.20\pm0.61$ \\
$B>0$, $B<0$ ($40<A<800$) & $-1.83\pm0.10$ & $0.27\pm0.13$ \\
$B>0$, $B<0$ ($A<40$) & $-3.44\pm0.06$ & $-0.99\pm0.08$ \\ \hline
$North$, $S\!outh$ ($B>0$) & $3.99\pm0.07$ & $5.63\pm0.09$\\
$North$, $S\!outh$ ($B<0$) & $-4.60\pm0.08$ & $-3.61\pm0.10$\\ \hline
$East$, $West$ & $-3.23\pm0.05$ & $-2.28\pm0.07$ \\
$East$, $West$ ($B>0$, $North$) & $-3.67\pm0.10$ & $-3.28\pm0.13$\\
$East$, $West$ ($B<0$, $North$) & $-1.55\pm0.11$ & $-1.84\pm0.14$\\ \hline
\end{tabular}
%\end{center}
\par
\end{table}