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

   Clinical |
Estimate of |
  Gestation |
    Used or |
  Gestation |
    Imputed |
       Flag |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        734        7.34        7.34
          2 |      1,260       12.60       19.94
          . |      8,006       80.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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