Frequencies for first 10,000 rows of exam variable in nhamcsopd2009 dataset :

    was any |
    type of |
       exam |
ordered/pro |
    vided - |
    recoded |
       from |
proc1-proc9 |
      using |
  icd-9-cm  |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      8,166       81.66       81.66
        yes |      1,834       18.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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