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

    AIR BAG |
AVAILABILIT |
 Y/FUNCTION |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        649        6.49        6.49
          1 |      1,240       12.40       18.89
          2 |          6        0.06       18.95
          8 |          4        0.04       18.99
          9 |         80        0.80       19.79
         20 |        528        5.28       25.07
         28 |          2        0.02       25.09
         29 |      1,913       19.13       44.22
         30 |      5,251       52.51       96.73
         31 |          4        0.04       96.77
         32 |          3        0.03       96.80
         99 |        320        3.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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