Frequencies for first 10,000 rows of p4 variable in miper dataset :

         p4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,466       74.66       74.66
          1 |         30        0.30       74.96
          2 |         70        0.70       75.66
          3 |         50        0.50       76.16
          4 |         62        0.62       76.78
          5 |         54        0.54       77.32
          6 |         70        0.70       78.02
          7 |         77        0.77       78.79
          8 |         70        0.70       79.49
          9 |         86        0.86       80.35
         10 |         97        0.97       81.32
         11 |        109        1.09       82.41
         12 |         96        0.96       83.37
         13 |        102        1.02       84.39
         14 |        130        1.30       85.69
         15 |        123        1.23       86.92
         16 |        113        1.13       88.05
         17 |        107        1.07       89.12
         18 |         94        0.94       90.06
         19 |        120        1.20       91.26
         20 |        108        1.08       92.34
         21 |        101        1.01       93.35
         22 |         91        0.91       94.26
         23 |         81        0.81       95.07
         24 |         68        0.68       95.75
         25 |         64        0.64       96.39
         26 |         63        0.63       97.02
         27 |         40        0.40       97.42
         28 |         43        0.43       97.85
         29 |         35        0.35       98.20
         30 |         32        0.32       98.52
         31 |         31        0.31       98.83
         32 |         28        0.28       99.11
         33 |         19        0.19       99.30
         34 |         12        0.12       99.42
         35 |          7        0.07       99.49
         36 |          5        0.05       99.54
         37 |          9        0.09       99.63
         38 |          7        0.07       99.70
         39 |          5        0.05       99.75
         40 |          4        0.04       99.79
         41 |          5        0.05       99.84
         42 |          6        0.06       99.90
         43 |          1        0.01       99.91
         44 |          4        0.04       99.95
         45 |          1        0.01       99.96
         50 |          1        0.01       99.97
         51 |          1        0.01       99.98
         67 |          1        0.01       99.99
         77 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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