\begin{table}%t2
\caption{\label{tab:surveys}Instrumental properties of the treated surveys.}
%\centerline
 {\small \begin{tabular}{ccrccccc}
\hline\hline
{Survey} & {$\delta$ range} & {FOV} & CCD Pixel size & {$m_{\rm V}$ Range} & {$\delta$ \& $m_{\rm V}$} & {$\delta$, $m_{\rm V}$ \& ${\Delta}m_{\rm V}$} & {$\delta$, $m_{\rm V}$, ${\Delta}m_{\rm V}$ \& MS} \\
&  & & & {[Mag.]} & {Limited sample} & {Limited sample} & {Limited sample} \\
\hline
BEST      & $ -16^\circ< \delta < 90^\circ$ &  $3.1^\circ$ & \hspace{0.1cm} $5.5~\arcsec/$mm & $8 < m_{\rm V} < 14$ & 546~382 \ \tiny{(52.94\%)} & 516~524 \ \tiny{(50.05\%)} & 222~854 \ \tiny{(21.59\%)} \\
XO        & $ -39^\circ < \delta < 90^\circ$ &  $7.2^\circ$ &      $25.4~\arcsec/$mm & $9 < m_{\rm V} < 12$ & 620~477 \ \tiny{(60.12\%)} & 597~842 \ \tiny{(57.93\%)} & 263~213 \ \tiny{(25.51\%)} \\
SuperWASP & $ -44^\circ< \delta < 90^\circ$ &  $7.8^\circ$ &      $13.8~\arcsec/$mm          & $7 < m_{\rm V} < 12$ & 745~227 \ \tiny{(72.21\%)} & 703~707 \ \tiny{(68.19\%)} & 311~404 \ \tiny{(30.18\%)}\\
HATNet    & $ -28^\circ< \delta < 90^\circ$ &  $8.3^\circ$ &      $14.0~\arcsec/$mm          & $7 < m_{\rm V} < 12$ & 721~473 \ \tiny{(69.91\%)} & 686~927 \ \tiny{(66.56\%)} & 283~350 \ \tiny{(27.46\%)}\\
\hline
  \end{tabular}}
\medskip
In the last three columns we list the reduced Tycho master sample of 1~031~992 stars after we applied the subsequent boundary conditions: the survey's sky-coverage ($\delta$ range), its $m_{\rm V}$ limitation, magnitude variation ${\Delta}m_{\rm V} > 0.01^{\rm m}$ for the transit of a Jupiter-sized object around the $i$th star in a pixel, and the boundary conditions for MS stars, for which the empirical relationships hold (see Sect.~\ref{sub:derivation}). In braces we indicate the portion of the Tycho master sample.
\end{table}