Frequencies for first 10,000 rows of mm_icu variable in natl2013 dataset :

   Admit to |
  Intensive |
       Care |
626=f_mm_ic |
        u R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,755       97.55       97.55
          U |        227        2.27       99.82
          Y |         18        0.18      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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