Frequencies for first 10,000 rows of opdof09x variable in h126f dataset :

 DOCTOR AMT |
  PAID, OTH |
    FEDERAL |
  (IMPUTED) |      Freq.     Percent        Cum.
------------+-----------------------------------
         -1 |         21        0.21        0.21
          0 |      9,979       99.79      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Feb 2018