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\begin{document}
\begin{tabular}{lc}
\hline\hline
Source  & Value (\%) \\
\hline
\\ [-2.0ex]
Mean $\delta m$     & $^{+4.9}_{-6.4}$ \\
\\ [-2.2ex]
Signal resolution   & 3.0 \\
Combinatorial background shape    & 12.6 \\
\hline
$\epsilon({\rm High~S/B})/\epsilon({\rm Low~S/B})$       &  2.0  \\
Slow $\pi\xspace\xspace^-\xspace$ efficiency            &  2.3 \\
$\Lambda\xspace^0_ b\xspace\xspace\xspace$ normalization mode yield    &  1.0 \\
Simulated sample size             &  2.1 \\
\hline
\\ [-1.8ex]
Total for signal significance            & $^{+13.9}_{-14.5}$ \\
\\ [-1.8ex]
Total for $r_s$            & $^{+14.4}_{-15.0}$ \\
\\ [-2.0ex]
\hline\hline
\end{tabular}
\end{document}
