Frequencies for first 10,000 rows of prov2135 variable in pos1993 dataset :

   srv: ekg |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,608       96.08       96.08
          0 |         24        0.24       96.32
          1 |        109        1.09       97.41
          2 |        256        2.56       99.97
          3 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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