Frequencies for first 10,000 rows of ekg_srvc_cd variable in pos2005 dataset :

   srv: ekg |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,323       93.23       93.23
          0 |         43        0.43       93.66
          1 |        205        2.05       95.71
          2 |        409        4.09       99.80
          3 |         20        0.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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