\begin{table}%t2
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\par
  \caption{Pulsar survey speed comparison.
    \label{tab:surveys}}
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\hline\hline
Pulsar Survey & $A_{\rm eff}/T_{\rm sys}$ & $\nu$ & $BW$ & $\Omega_{d^2}$ & $\Sigma_{\rm PSR}$\\ 
\ & (m$^2$/K) & (GHz) & (GHz) & (deg$^2$) & \\
\hline 
Parkes 20~cm Multi-beam & 70 & 1.4 & 0.30 & 0.41 & 180\\ 
Parkes 70~cm............ &  32 & 0.41 & 0.03 & 0.39 & 290\\
Arecibo 20~cm ALFA...... & 805 & 1.4 & 0.3 & 0.02 & 1100\\
WSRT 90~cm \eight....... & 31 & 0.33 & 0.01 & 4.2 & 2230  \\ 
ASKAP 35~cm 8k-beam..... & 32 & 0.85 & 0.3 & 6 & 3300 \\
meerKAT 30~cm 1k-beam & 180 & 1.0 & 0.5 & 0.5 & 8300 \\
SKA 35~cm 1k-beam....... & 2000 & 0.85 & 0.3 & 0.75 & 1.6$~\times~10^6$ \\
\hline 
\end{tabular}
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\end{table}