Frequencies for first 10,000 rows of proc variable in nhamcsed1997 dataset :

       were |
 procedures |
  provided? |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      5,588       55.88       55.88
        Yes |      4,412       44.12      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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