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

has patient been seen in |
     this clinic before? |      Freq.     Percent        Cum.
-------------------------+-----------------------------------
Yes, established patient |      7,987       79.87       79.87
         No, new patient |      1,831       18.31       98.18
                   Blank |        182        1.82      100.00
-------------------------+-----------------------------------
                   Total |     10,000      100.00

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