Frequencies for first 10,000 rows of ab_nicu variable in natlterr2012 dataset :

  Admission |
to NICU RFP |
630=f_ab_ni |
       cu R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,163       11.63       11.63
          N |      8,014       80.14       91.77
          U |        426        4.26       96.03
          Y |        397        3.97      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 5 May 2016