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

      TOWED |
   TRAILING |
       UNIT |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,705       87.05       87.05
          1 |        438        4.38       91.43
          2 |         30        0.30       91.73
          3 |          1        0.01       91.74
          4 |          2        0.02       91.76
          9 |        129        1.29       93.05
          . |        695        6.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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