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

         p4 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,483       74.83       74.83
          1 |         45        0.45       75.28
          2 |         57        0.57       75.85
          3 |         35        0.35       76.20
          4 |         51        0.51       76.71
          5 |         57        0.57       77.28
          6 |         48        0.48       77.76
          7 |         60        0.60       78.36
          8 |         59        0.59       78.95
          9 |         78        0.78       79.73
         10 |         88        0.88       80.61
         11 |         87        0.87       81.48
         12 |        109        1.09       82.57
         13 |         97        0.97       83.54
         14 |        102        1.02       84.56
         15 |        119        1.19       85.75
         16 |        117        1.17       86.92
         17 |        109        1.09       88.01
         18 |        104        1.04       89.05
         19 |        126        1.26       90.31
         20 |         92        0.92       91.23
         21 |        112        1.12       92.35
         22 |         97        0.97       93.32
         23 |        102        1.02       94.34
         24 |         87        0.87       95.21
         25 |         67        0.67       95.88
         26 |         63        0.63       96.51
         27 |         45        0.45       96.96
         28 |         43        0.43       97.39
         29 |         34        0.34       97.73
         30 |         43        0.43       98.16
         31 |         28        0.28       98.44
         32 |         16        0.16       98.60
         33 |         19        0.19       98.79
         34 |         18        0.18       98.97
         35 |         17        0.17       99.14
         36 |         17        0.17       99.31
         37 |         13        0.13       99.44
         38 |          5        0.05       99.49
         39 |          7        0.07       99.56
         40 |          8        0.08       99.64
         41 |         12        0.12       99.76
         42 |          6        0.06       99.82
         43 |          4        0.04       99.86
         44 |          2        0.02       99.88
         45 |          1        0.01       99.89
         46 |          1        0.01       99.90
         47 |          1        0.01       99.91
         48 |          1        0.01       99.92
         50 |          1        0.01       99.93
         51 |          1        0.01       99.94
         54 |          2        0.02       99.96
         59 |          1        0.01       99.97
         60 |          1        0.01       99.98
         63 |          1        0.01       99.99
         65 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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