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

   rollover |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,148       71.48       71.48
          1 |        946        9.46       80.94
          2 |      1,146       11.46       92.40
          . |        760        7.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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