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

     Impact |
Point-Princ |
       ipal |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        414        4.14        4.14
          1 |        510        5.10        9.24
          2 |        214        2.14       11.38
          3 |        790        7.90       19.28
          4 |        106        1.06       20.34
          5 |        102        1.02       21.36
          6 |        261        2.61       23.97
          7 |        163        1.63       25.60
          8 |         99        0.99       26.59
          9 |        753        7.53       34.12
         10 |         99        0.99       35.11
         11 |        634        6.34       41.45
         12 |      3,690       36.90       78.35
         13 |      1,126       11.26       89.61
         14 |        103        1.03       90.64
         15 |         32        0.32       90.96
         99 |        123        1.23       92.19
          . |        781        7.81      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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