Frequencies for first 10,000 rows of ab_aven6 variable in natlterr2010 dataset :

   Assisted |
Ventilation |
 >6 hrs RFP |
629=f_ab_ve |
      nt6 R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,656       46.56       46.56
          N |      4,272       42.72       89.28
          U |        976        9.76       99.04
          Y |         96        0.96      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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