Frequencies for first 10,000 rows of therprev variable in nhamcsopd1998 dataset :

       were |
therapeutic |
 /prev serv |
ordered/pro |
     vided? |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      5,060       50.60       50.60
        Yes |      4,925       49.25       99.85
  No answer |         15        0.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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