Frequencies for first 10,000 rows of uab_alcoh variable in natlterr2003 dataset :

      Fetal |
    Alcohol |
 Syndrome U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          9        0.09        0.09
          2 |      9,967       99.67       99.76
          8 |         23        0.23       99.99
          9 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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