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

     Impact |
Point-Princ |
       ipal |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,056       10.56       10.56
          1 |        507        5.07       15.63
          2 |        142        1.42       17.05
          3 |        695        6.95       24.00
          4 |         92        0.92       24.92
          5 |         92        0.92       25.84
          6 |        334        3.34       29.18
          7 |        105        1.05       30.23
          8 |        114        1.14       31.37
          9 |        762        7.62       38.99
         10 |        115        1.15       40.14
         11 |        603        6.03       46.17
         12 |      4,197       41.97       88.14
         13 |         80        0.80       88.94
         14 |        226        2.26       91.20
         15 |         25        0.25       91.45
         16 |         14        0.14       91.59
         99 |         65        0.65       92.24
          . |        776        7.76      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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