Frequencies for first 10,000 rows of seat_pos variable in person dataset :

    Seating |
   Position |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        798        7.98        7.98
         11 |      5,312       53.12       61.10
         12 |        226        2.26       63.36
         13 |      1,778       17.78       81.14
         18 |         48        0.48       81.62
         19 |         69        0.69       82.31
         21 |        386        3.86       86.17
         22 |        131        1.31       87.48
         23 |        370        3.70       91.18
         28 |         33        0.33       91.51
         29 |         66        0.66       92.17
         31 |          4        0.04       92.21
         32 |          5        0.05       92.26
         33 |          5        0.05       92.31
         38 |          1        0.01       92.32
         39 |          6        0.06       92.38
         50 |         31        0.31       92.69
         51 |        251        2.51       95.20
         52 |         94        0.94       96.14
         53 |         34        0.34       96.48
         54 |          2        0.02       96.50
         55 |         33        0.33       96.83
         99 |        317        3.17      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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