Frequencies for first 10,000 rows of proc variable in nhamcsed2010 dataset :

  Were procedures |
       performed? |      Freq.     Percent        Cum.
------------------+-----------------------------------
               no |      5,049       50.49       50.49
              yes |      4,648       46.48       96.97
entire item blank |        303        3.03      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016