\begin{table}%t4
\caption{\label{t4}Number of WD candidates detected and space densities. The errors are
calculated using small number statistics from Gehrels (1986).}
%\centering
\par
\begin{tabular}{ccccccc}
\hline
\hline
 &  $V_{\rm lim}=21$ &    $V_{\rm lim}=22$ & $V_{\rm lim}=23$& $d<357$ pc    & $d<566$ pc    & $d<897$ pc \\
 & & & & ($z<273$ pc)  & ($z<434$ pc)  & ($z<687$ pc)\\ 
\hline
 $-0.35 < B-V <-0.25$ &   0 &  0 &  1 &    0 &  0 &  0 \\
 $-0.25 < B-V < -0.15$ &  0 &  1 &  1 &          0 &  0 &  0 \\
 $-0.15 < B-V < -0.05$ &  1 &  1 &  2 &          0 &  0 &  1 \\
 $-0.05 < B-V < 0.05$ &  0 &  1 &  1 &          0 &  0 &  0 \\
 $0.05 < B-V < 0.15$ &  2 &  4 &  8 &          0 &  1 &  2 \\
 $0.15 < B-V < 0.25$ &  5 &  6 &  11 &  3 &  5 &  6 \\
 $0.25 < B-V < 0.35$ &  5 &  6 &  8 &   5 &  6 &  8 \\
\hline
TOT &  13 &  19 &  32 &  8 &  12 &  17 \\
\hline
space density (pc$^{-3})$ & & &
&  (3.46$\pm$$^{1.71}_{1.20}$) $\times$ 10$^{-3}$
&  (1.31$\pm$$^{0.50}_{0.37}$) $\times$ 10$^{-3}$
&  (4.64$\pm$$^{1.42}_{1.11}$) $\times$ 10$^{-4}$ \\
\hline
\end{tabular} 
\end{table}