Frequencies for first 10,000 rows of therprev variable in nhamcsopd1997 dataset :

       were |
therapeutic |
 /prev serv |
ordered/pro |
     vided? |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      5,175       51.75       51.75
        Yes |      4,811       48.11       99.86
  No answer |         14        0.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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