Frequencies for first 10,000 rows of exp_dtstr variable in drug2018q4 dataset :

  Expiration date |
           of the |
    drug.Multiple |
  dates possible. |      Freq.     Percent        Cum.
------------------+-----------------------------------
                  |     10,000      100.00      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Mar 2019