\begin{table} %t4
 %\centering
\par
 \caption{The distribution of observations of
  perturbed asteroids. In the columns $N_{1}$, $N_{2}$, $N_{3}$, $N_{4}$, $N_{5}$ are given number of observations,
   number of discarded preenc. observations, number of used preenc. observations, number of
  discarded postenc. observations and number of used postenc. observations.  $T_{1}$ and $T_{2}$ are
   time intervals covered by preencounter and postencounter observations. The standard
   deviations  of orbital residuals are given in the last column.}\label{tab4}
    \begin{tabular}{ccccccccc} 
\par
      \hline \hline 
       Perturbed& $ N_{1}$   & $N_{2}$&$N_{3}$ &$T_{1}$  &$N_{4}$&$N_{5}$& $T_{2}$&rms   \\
\par
       asteroid&  &   &  &  &  &  & &[~$\arcsec$~]  \\
\par
            \hline
   ~(3057) Malaren   & 307& 3 & 11& 1952--1981&15  &278  & 1983--2004&0.63 \\
  ~~(5205) 1988CU7  &321& 2 & 3 & 1954--1961&36 &280  & 1988--2003&0.58 \\
  ~(8331) Dawkins    & 368& 2 & 5 & 1982&16           &345  & 1990--2003&0.68 \\
  (21225) 1995GQ1  & 180& 0  & 4 &  1972 &  5    &171  & 1995--2003&0.66 \\
\par
            \hline
   \end{tabular}
   \end{table}