Frequencies for first 10,000 rows of impact2 variable in person dataset :

     Impact |
Point-Princ |
       ipal |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        981        9.81        9.81
          1 |        452        4.52       14.33
          2 |        114        1.14       15.47
          3 |        786        7.86       23.33
          4 |         83        0.83       24.16
          5 |         98        0.98       25.14
          6 |        281        2.81       27.95
          7 |         88        0.88       28.83
          8 |         99        0.99       29.82
          9 |        769        7.69       37.51
         10 |         77        0.77       38.28
         11 |        491        4.91       43.19
         12 |      4,019       40.19       83.38
         13 |        626        6.26       89.64
         14 |        115        1.15       90.79
         15 |          7        0.07       90.86
         99 |         49        0.49       91.35
          . |        865        8.65      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Apr 2016