\begin{table}%t3
\caption{\label{t_evol}Bar fractions and properties as a function of $z$.}
\small%\centerline
 {
\begin{tabular}{c c c c}
\hline \hline
Spec-$z$ & $0.4<z\le0.55$ & $0.55<z\le0.7$ & $0.7<z\le0.8$ \\
\hline
\# of objects & 87 & 78 & 76 \\
bar fraction & $30\%$ & $26\%$ & $22\%$ \\
$\langle a_{\rm bar}\rangle$ [kpc] & 3.38 & 3.83 & 3.37 \\
$\langle e_{\rm bar}\rangle$ [kpc] & 0.54 & 0.53 & 0.52 \\
\hline
\\
\end{tabular}}
\medskip
Notes: the bar fraction and average bar sizes and ellipticities in three spectroscopically based redshift bins.
\end{table}