Frequencies for first 10,000 rows of ab_nicu variable in natlterr2011 dataset :

  Admission |
to NICU RFP |
630=f_ab_ni |
       cu R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,536       25.36       25.36
          N |      5,948       59.48       84.84
          U |      1,094       10.94       95.78
          Y |        422        4.22      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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