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

    AIR BAG |
AVAILABILIT |
 Y/FUNCTION |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        693        6.93        6.93
          1 |        976        9.76       16.69
          2 |          1        0.01       16.70
          9 |          1        0.01       16.71
         20 |        275        2.75       19.46
         28 |          1        0.01       19.47
         29 |        808        8.08       27.55
         30 |      6,288       62.88       90.43
         31 |          2        0.02       90.45
         99 |        955        9.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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