Frequencies for first 10,000 rows of proc variable in nhamcsed2015 dataset :

Were procedures provided at this visit? |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
                                     No |      5,433       54.33       54.33
                                    Yes |      4,305       43.05       97.38
Entire item blank, including 'None' box |        262        2.62      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Nov 2017