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

  Admission |
to NICU RFP |
630=f_ab_ni |
       cu R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,656       46.56       46.56
          N |      3,949       39.49       86.05
          U |        976        9.76       95.81
          Y |        419        4.19      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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