Frequencies for first 10,000 rows of nprevist variable in linkco1991us_num dataset :

      Total |
  Number of |
   Prenatal |
     Visits |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        794        7.94        7.94
          1 |        296        2.96       10.90
          2 |        412        4.12       15.02
          3 |        564        5.64       20.66
          4 |        746        7.46       28.12
          5 |        757        7.57       35.69
          6 |        733        7.33       43.02
          7 |        519        5.19       48.21
          8 |        588        5.88       54.09
          9 |        378        3.78       57.87
         10 |        912        9.12       66.99
         11 |        279        2.79       69.78
         12 |        814        8.14       77.92
         13 |        282        2.82       80.74
         14 |        319        3.19       83.93
         15 |        412        4.12       88.05
         16 |        120        1.20       89.25
         17 |         55        0.55       89.80
         18 |         66        0.66       90.46
         19 |         22        0.22       90.68
         20 |        180        1.80       92.48
         21 |          6        0.06       92.54
         22 |         15        0.15       92.69
         23 |          4        0.04       92.73
         24 |         10        0.10       92.83
         25 |         30        0.30       93.13
         26 |          3        0.03       93.16
         27 |          2        0.02       93.18
         28 |          1        0.01       93.19
         29 |          2        0.02       93.21
         30 |         32        0.32       93.53
         32 |          3        0.03       93.56
         33 |          1        0.01       93.57
         35 |          4        0.04       93.61
         39 |          2        0.02       93.63
         40 |          5        0.05       93.68
         44 |          1        0.01       93.69
         49 |          1        0.01       93.70
         99 |        630        6.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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