Frequencies for first 10,000 rows of gestat10 variable in natl1993 dataset :

  Gestation |
  Recode 10 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          8        0.08        0.08
          2 |         90        0.90        0.98
          3 |        161        1.61        2.59
          4 |        670        6.70        9.29
          5 |        425        4.25       13.54
          6 |      4,254       42.54       56.08
          7 |      2,074       20.74       76.82
          8 |      1,198       11.98       88.80
          9 |      1,114       11.14       99.94
         10 |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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