\hline & Data  & MC   \\\hline
  ee & 7483 & 6398   \\ 
  \mu\mu   & 7417 & 10292   \\ 
  OF   & 16557 & 15213   \\ 
  SF   & 14900 & 16672   \\ \hline
  R_{\mathrm{SF/OF}}   & 0.900 \pm 0.010 & 1.092 \pm 0.036  \\ \hline