Frequencies for first 10,000 rows of rollover variable in vehicle dataset :

   Rollover |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,011       80.11       80.11
          1 |        796        7.96       88.07
          2 |      1,193       11.93      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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