Frequencies for first 10,000 rows of nprev28 variable in natl1978 dataset :

  Number of |
   Prenatal |
     Visits |
     Recode |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        124        1.24        1.24
          2 |        123        1.23        2.47
          3 |        198        1.98        4.45
          4 |        269        2.69        7.14
          5 |        390        3.90       11.04
          6 |        487        4.87       15.91
          7 |        656        6.56       22.47
          8 |        525        5.25       27.72
          9 |        681        6.81       34.53
         10 |        697        6.97       41.50
         11 |      1,142       11.42       52.92
         12 |        933        9.33       62.25
         13 |      1,606       16.06       78.31
         14 |        592        5.92       84.23
         15 |        730        7.30       91.53
         16 |        388        3.88       95.41
         17 |        133        1.33       96.74
         18 |         44        0.44       97.18
         19 |         71        0.71       97.89
         20 |         10        0.10       97.99
         21 |         68        0.68       98.67
         22 |          8        0.08       98.75
         23 |         14        0.14       98.89
         24 |          2        0.02       98.91
         25 |          1        0.01       98.92
         26 |         13        0.13       99.05
         27 |          9        0.09       99.14
         28 |         86        0.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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