Frequencies for first 10,000 rows of f_apgar5 variable in natl2009 dataset :

 5 - minute |
      Apgar |
    (apgar5 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         40        0.40        0.40
          1 |      9,960       99.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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