Frequencies for first 10,000 rows of icu_srvc_cd variable in pos2007 dataset :

 srv: icu - |
medical/sur |
      gical |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,682       86.82       86.82
          0 |        513        5.13       91.95
          1 |        768        7.68       99.63
          2 |         29        0.29       99.92
          3 |          8        0.08      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017