\documentclass{article}
\begin{document}
\begin{table}
\small
\centering
\begin{tabular}{c|cc}
Source & Variation up (Stat. up) \% & Variation down (Stat. down) \% \\ \hline 
muR\_muF-ttV\_SR2L & 46.4816 & 12.7054 \\ 
muR\_muF-ttV\_tW2L\_CRtt & -11.4966 & -76.5255 \\ 
muR\_muF-ttV\_tW2L\_CRttZ & 83.5626 & 71.8648 \\ 
muR\_muF-ttV\_tW2L\_CRWZ & 82.7994 & 71.7509 \\ 
muR\_muF-ttV\_tW2L\_VRtt & -10.0093 & -75.1975 \\ 
muR\_muF-ttV\_tW2L\_VR3L & 83.0177 & 71.1968 \\ 
\end{tabular}
\end{table}
\end{document}
