Frequencies for first 10,000 rows of ekg_srvc_cd variable in pos2000 dataset :

   srv: ekg |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,327       93.27       93.27
          0 |         41        0.41       93.68
          1 |        174        1.74       95.42
          2 |        451        4.51       99.93
          3 |          7        0.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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