\begin{table}%t1
\caption{\label{table:2}Standard deviations and mean value of $P_{\rm tot}$.}
%\centering
\small
\begin{tabular}{l c c c}
\hline \hline
Altitude [km] & --98 & 182 & 462 \\
Standard deviation of $P_{\rm tot}$ in non-magnetic regions  ($\sigma_{\rm NM}$) [cgs]& 27~703.0  &  9707.59  & 1055.04 \\
Standard deviation of $P_{\rm tot}$ in magnetic regions  ($\sigma_{\rm M}$) [cgs]& 32~709.4  & 7950.80  & 2151.41 \\
Mean value of $P_{\rm tot}$ in non-magnetic regions ($\overline{NM}$) [cgs]& 254~220.0 &  57~750.9  & 4901.33 \\
Mean value of $P_{\rm tot}$ in magnetic regions ($\overline{M}$) [cgs]& 249~696.0 & 47~409.8  &  8626.20 \\
$\sigma_{\rm NM}$/$\overline{NM}$ & 0.108 & 0.168  & 0.215 \\
$\sigma_{\rm M}$/$\overline{M}$ & 0.130 & 0.167  & 0.249 \\
 \hline
 \end{tabular}
 \end{table}