Frequencies for low variable in drg1999 dataset :

 Low Volume |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        472       92.37       92.37
          * |         39        7.63      100.00
------------+-----------------------------------
      Total |        511      100.00

by Jean Roth , jroth@nber.org , 22 Apr 2016