\begin{table}%t4!
\caption{\label{surveysummary}Survey summary.} 
%\centering
\par
%renewcommand{\footnoterule}{}
\begin{tabular}{lllrrr}
\hline\hline
 Target category & Definition$^a$
 & Orbital element ranges$^b$
 & $n_{\rm obj}$$^c$
 & $n_{\rm obs}$$^d$
 & $n_{\rm tot}$$^e$\\
\hline
 Themis family   & $\delta v^{\prime}=70$~m~s$^{-1}$ with respect to 24 Themis         & $3.04 < a < 3.27$, $0.05 < e < 0.23$, $0.0 < i < 3.1$ & 342 & 389 & 2271 \\
 Low-$i$ asteroids$^f$ & $3.0~{\rm AU}<a<3.3~{\rm AU}$, $e<0.3$, $i<3.0^{\circ}$, $H_{\rm V}>14.0$ & $3.09 < a < 3.21$, $0.03 < e < 0.30$, $0.1 < i < 2.9$ & 426 & 476 & 10~929 \\
 Karin cluster   & $\delta v^{\prime}=10$~m~s$^{-1}$ with respect to 832 Karin         & $2.86 < a < 2.87$, $0.00 < e < 0.09$, $1.0 < i < 3.2$ & 15 & 15 &  130 \\
 Koronis family$^g$  & $\delta v^{\prime}=50$~m~s$^{-1}$ with respect to 158 Koronis        & $2.83 < a < 2.95$, $0.00 < e < 0.12$, $0.7 < i < 3.3$ & 131 & 136 & 2565 \\
 Veritas family  & $\delta v^{\prime}=40$~m~s$^{-1}$ with respect to 490 Veritas        & $3.15 < a < 3.18$, $0.02 < e < 0.11$, $7.9 < i < 10.6$ & 42 & 45 &  324 \\
 \\
 Total       &  {\ldots} & {\ldots}  & 599 & 657 & 13~818 \\
\hline
\end{tabular}
\smallskip
$^a$ Criteria used to select target list from general
          asteroid population, where family and cluster members
          are selected using hierarchical clustering
      \citep{zap90,zap94} and the maximum allowable
      $\delta v$ value, $\delta v^{\prime}$, with respect to each family's or
      cluster's reference asteroid, is listed.  \\
$^b$ Osculating orbital element ranges for the target samples in this
          survey, where semimajor axis distances are in AU and
          inclination values are in degrees.  \\
$^c$   Number of unique objects observed belonging to each category.\\
$^d$ Number of observations of objects belonging to each category (where multiple
          observations of single targets are counted independently).  \\
$^e$ Total number of known potential targets belonging to each category (as of 2009 April 1).   \\
$^f$ Includes all Themis family members.  \\
$^g$ Includes all Karin cluster members.  \\
\end{table}