Frequencies for first 10,000 rows of ab_aven6 variable in natlterr2015 dataset :

   Assisted |
Ventilation |
  > 6 hrs Y |
        Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,078       10.78       10.78
          N |      8,713       87.13       97.91
          U |         94        0.94       98.85
          Y |        115        1.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Oct 2016