Frequencies for seat_pos variable in person dataset :

    SEATING |
   POSITION |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        193       17.92       17.92
         11 |        625       58.03       75.95
         12 |          1        0.09       76.04
         13 |        147       13.65       89.69
         21 |         53        4.92       94.61
         22 |         11        1.02       95.64
         23 |         23        2.14       97.77
         28 |          3        0.28       98.05
         29 |          1        0.09       98.14
         51 |          2        0.19       98.33
         52 |         17        1.58       99.91
         53 |          1        0.09      100.00
------------+-----------------------------------
      Total |      1,077      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016