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

         p4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,522       75.22       75.22
          1 |         35        0.35       75.57
          2 |         69        0.69       76.26
          3 |         58        0.58       76.84
          4 |         52        0.52       77.36
          5 |         55        0.55       77.91
          6 |         79        0.79       78.70
          7 |         81        0.81       79.51
          8 |         77        0.77       80.28
          9 |         91        0.91       81.19
         10 |         96        0.96       82.15
         11 |        102        1.02       83.17
         12 |         99        0.99       84.16
         13 |         96        0.96       85.12
         14 |        100        1.00       86.12
         15 |        114        1.14       87.26
         16 |        115        1.15       88.41
         17 |        115        1.15       89.56
         18 |        129        1.29       90.85
         19 |         93        0.93       91.78
         20 |         87        0.87       92.65
         21 |         87        0.87       93.52
         22 |         79        0.79       94.31
         23 |         70        0.70       95.01
         24 |         66        0.66       95.67
         25 |         60        0.60       96.27
         26 |         48        0.48       96.75
         27 |         55        0.55       97.30
         28 |         43        0.43       97.73
         29 |         39        0.39       98.12
         30 |         34        0.34       98.46
         31 |         22        0.22       98.68
         32 |         22        0.22       98.90
         33 |         16        0.16       99.06
         34 |         14        0.14       99.20
         35 |          9        0.09       99.29
         36 |          2        0.02       99.31
         37 |          8        0.08       99.39
         38 |         12        0.12       99.51
         39 |          4        0.04       99.55
         40 |          6        0.06       99.61
         41 |          6        0.06       99.67
         42 |          4        0.04       99.71
         43 |          5        0.05       99.76
         44 |          3        0.03       99.79
         45 |          3        0.03       99.82
         46 |          3        0.03       99.85
         47 |          4        0.04       99.89
         48 |          4        0.04       99.93
         49 |          1        0.01       99.94
         50 |          1        0.01       99.95
         52 |          1        0.01       99.96
         53 |          1        0.01       99.97
         55 |          1        0.01       99.98
         58 |          1        0.01       99.99
         70 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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