Frequencies for first 10,000 rows of nprev12 variable in natl1993 dataset :

  Number of |
   Prenatal |
     Visits |
     Recode |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         98        0.98        0.98
          2 |        136        1.36        2.34
          3 |        292        2.92        5.26
          4 |        689        6.89       12.15
          5 |      1,007       10.07       22.22
          6 |      1,993       19.93       42.15
          7 |      2,386       23.86       66.01
          8 |      1,614       16.14       82.15
          9 |      1,136       11.36       93.51
         10 |        250        2.50       96.01
         11 |        355        3.55       99.56
         12 |         44        0.44      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015