Frequencies for first 10,000 rows of dmp variable in nhamcsopd2008 dataset :

      status of patient enrollment in a |
             disease management program |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
                                  blank |        429        4.29        4.29
                                unknown |      2,694       26.94       31.23
                         not applicable |      4,968       49.68       80.91
                     currently enrolled |      1,169       11.69       92.60
ordered/advised to enroll at this visit |         64        0.64       93.24
                           not enrolled |        676        6.76      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

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