Frequencies for first 10,000 rows of rdlgy_srvc_cd variable in pos2012 dataset 

   Service: |
  Radiology |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |      9,608       96.08       96.08
          1 |         81        0.81       96.89
          2 |        296        2.96       99.85
          3 |         15        0.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016