\begin{Schunk}
\begin{Sinput}
 pctable(yobs ~ x, data = dat)
\end{Sinput}
\begin{Soutput}
Count (column %)
     x
yobs  0          1          Sum 
  0   430(88.1%) 114(22.3%) 544 
  1   58(11.9%)  398(77.7%) 456 
  Sum 488        512        1000
\end{Soutput}
\end{Schunk}
