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

   Rollover |
       Type |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,873       68.73       68.73
          1 |      1,852       18.52       87.25
          2 |        303        3.03       90.28
          9 |         43        0.43       90.71
          . |        929        9.29      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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