Frequencies for first 10,000 rows of prov2885 variable in pos2002 dataset :

    type of |
    control |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        101        1.01        1.01
         01 |      1,947       19.47       20.48
         02 |      1,142       11.42       31.90
         03 |      2,912       29.12       61.02
         04 |      1,418       14.18       75.20
         05 |        505        5.05       80.25
         06 |        942        9.42       89.67
         07 |        275        2.75       92.42
         08 |        197        1.97       94.39
         09 |         15        0.15       94.54
         10 |          4        0.04       94.58
         11 |         11        0.11       94.69
         12 |          8        0.08       94.77
         13 |          5        0.05       94.82
         1A |         48        0.48       95.30
         1B |        154        1.54       96.84
         1C |         23        0.23       97.07
         2A |          5        0.05       97.12
         2B |        286        2.86       99.98
         2C |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016