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

   rollover |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,904       69.04       69.04
          1 |      1,018       10.18       79.22
          2 |      1,353       13.53       92.75
          . |        725        7.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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