Frequencies for impact2 variable in person dataset :

  PRINCIPAL |
     IMPACT |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         38        2.95        2.95
          1 |         83        6.44        9.39
          2 |          2        0.16        9.55
          3 |         94        7.30       16.85
          4 |          4        0.31       17.16
          5 |          8        0.62       17.78
          6 |         39        3.03       20.81
          7 |         18        1.40       22.20
          9 |        112        8.70       30.90
         10 |         32        2.48       33.39
         11 |         38        2.95       36.34
         12 |        540       41.93       78.26
         13 |         58        4.50       82.76
          . |        222       17.24      100.00
------------+-----------------------------------
      Total |      1,288      100.00

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