Frequencies for p1 variable in miper dataset :

         p1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        567       68.64       68.64
          1 |          2        0.24       68.89
          2 |         11        1.33       70.22
          3 |          8        0.97       71.19
          4 |          8        0.97       72.15
          5 |         14        1.69       73.85
          6 |         12        1.45       75.30
          7 |          5        0.61       75.91
          8 |          8        0.97       76.88
          9 |          9        1.09       77.97
         10 |          7        0.85       78.81
         11 |          9        1.09       79.90
         12 |         10        1.21       81.11
         13 |          4        0.48       81.60
         14 |         11        1.33       82.93
         15 |         11        1.33       84.26
         16 |         15        1.82       86.08
         17 |         10        1.21       87.29
         18 |          9        1.09       88.38
         19 |         12        1.45       89.83
         20 |          5        0.61       90.44
         21 |          8        0.97       91.40
         22 |          6        0.73       92.13
         23 |          8        0.97       93.10
         24 |         12        1.45       94.55
         25 |          9        1.09       95.64
         26 |          5        0.61       96.25
         27 |          7        0.85       97.09
         28 |          3        0.36       97.46
         29 |          2        0.24       97.70
         30 |          3        0.36       98.06
         31 |          1        0.12       98.18
         32 |          5        0.61       98.79
         34 |          2        0.24       99.03
         35 |          3        0.36       99.39
         36 |          2        0.24       99.64
         40 |          2        0.24       99.88
         41 |          1        0.12      100.00
------------+-----------------------------------
      Total |        826      100.00

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