Frequencies for first 10,000 rows of nprev12 variable in natl1982 dataset :

  Number of |
   Prenatal |
     Visits |
     Recode |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        191        1.91        1.91
          2 |        454        4.54        6.45
          3 |        483        4.83       11.28
          4 |        867        8.67       19.95
          5 |      1,210       12.10       32.05
          6 |      1,892       18.92       50.97
          7 |      2,368       23.68       74.65
          8 |      1,343       13.43       88.08
          9 |        802        8.02       96.10
         10 |        163        1.63       97.73
         11 |        169        1.69       99.42
         12 |         58        0.58      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016