\begin{table}%t1
 \caption{\label{sample}The sample of CP stars used in this study and the available photometric data in the respective systems.} 
\small 
%\centerline
{
\begin{tabular}{l l l l l} 
\hline\hline \noalign{\smallskip}
CP class & Stars$^a$ & ${uvby}\beta$ & ${\it Geneva}$ & ${\it UBV}$$^b$  \\ 
\hline 
CP1 & 30/13  & 29 & 30 & 30 \\
CP2 & 79/51  & 78 & 76 & 63  \\
CP3 & 28/14  & 27 & 27 & 28  \\
CP4a & 20/15  & 20 & 20 & 20 \\
CP4b & 17/9 & 14 & 16 & 15 \\
CP4ab & 2/2 & 2 & 2 & 2 \\
\hline 
\end{tabular}}
\smallskip
$^a$  Stars in total / with average temperatures.\\
$^b$  Number of objects with a complete set is listed.
\end{table}