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\begin{document}
    
    
    
    \begin{tabular}{lcccccc} 
        \toprule
        & \multicolumn{6}{c}{Uncertainty ($\times 10^3$)} \\
        \midrule
        Source & $A_ K\xspace\xspace^{ K\xspace\xspace K\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ & $A_\pi\xspace\xspace^{ K\xspace\xspace K\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ & $A_ K\xspace\xspace^{\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ & $A_\pi\xspace\xspace^{\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ & $R_{ C\!P\xspace}^{ K\xspace\xspace K\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ & $R_{ C\!P\xspace}^{\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace\pi\xspace\xspace}$ \\
        \midrule
        Charmless background                          & $1.2$ & $<0.1$\phantom{00}  & $0.4$ & $<0.1$\phantom{00} & $13.9$ & $8.5$ \\
        External parameters                           & $1.5$ & $0.7$ & $1.5$ & $0.7$ & $4.0$ & $4.0$ \\
        Fixed yield fractions                         & $0.1$ & $<0.1$\phantom{00}  & $0.1$ & $<0.1$\phantom{00}  & $1.3$ & $1.4$ \\
        Mass shape                                    & $0.3$ & $<0.1$\phantom{00}  & $0.2$ & $<0.1$\phantom{00}  & $3.1$ & $3.1$ \\
        PID efficiency                                & $0.1$ & $<0.1$\phantom{00}  & $0.1$ & $<0.1$\phantom{00}  & $2.5$ & $1.6$ \\
        \midrule
        Total systematic                              & $2.0$ & $0.7$ & $1.6$ & $0.7$ & $15.1$ & $10.1$ \\
        \midrule
        Statistical                                   & $23.5$ & $5.5$ & $13.3$ & $3.1$ & $24.2$ & $14.3$ \\
        \bottomrule
    \end{tabular}
\end{document}
