\begin{table}[hpbt]
\begin{center}
\begin{tabular}{|c|c|c|c|c|c|c|c|c|c|}\hline
 Circuit   &Cost         &Cost             &CPU      &\multicolumn{3}{c|}{CLB}          &\multicolumn{3}{c|}{IOB} \\  
 \hfill    &(Lower bound)&(achieved)       &Cost     &\multicolumn{3}{c|}{utilization}  &\multicolumn{3}{c|}{utilization}\\ \cline{5-10}
\hfill     &(N\$)         &(N\$)             &(sec.)   &min.    &avg.    &max.            &min.     &avg.    &max. \\ \hline \hline
 c499      &2.00            &2.00            &4.2      &0.47    &0.56    &0.69            &0.95     &0.96    &0.97 \\ \hline 
 c1355     &2.00            &2.00            &4.4      &0.58    &0.58    &0.58            &0.95     &0.95    &0.95 \\ \hline    
 c1908     &3.00            &3.00            &15.9     &0.64    &0.77    &0.89            &0.64     &0.79    &0.98 \\ \hline 
 c2670     &4.00            &6.00            &51.6     &0.28    &0.55    &0.92            &0.74     &0.91    &1.00 \\ \hline 
 c3540     &6.00            &6.00            &59.4     &0.94    &0.97    &1.00            &0.74     &0.93    &1.00 \\ \hline
 c5315     &9.00            &11.00           &176.8    &0.55    &0.77    &0.89            &0.78     &0.91    &1.00 \\ \hline
 c6288     &14.00           &14.00           &306.2    &0.84    &0.94    &1.00            &0.43     &0.57    &0.69 \\ \hline 
 c7552     &10.00           &11.00           &239.1    &0.48    &0.88    &1.00            &0.72     &0.90    &1.00 \\ \hline
\end{tabular}
\caption{Partitioning using XC2000 devices of a single type (\$1.00/device)}
\label{tb:tb3}
\end{center}
\end{table}

