Frequencies for first 10,000 rows of ptprob2 variable in namcs2012 dataset :

    Share patient |
    problem lists |
   electronically |
  (not fax) with: |
       ambulatory |
       providers  |      Freq.     Percent        Cum.
------------------+-----------------------------------
   Not applicable |      6,561       65.61       65.61
Box is not marked |        907        9.07       74.68
    Box is marked |      2,532       25.32      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

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