Frequencies for first 10,000 rows of exp_dtstr variable in drug2014q2 dataset :

   Expiration date of the drug.Multiple |
                        dates possible. |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
                                        |      9,994       99.94       99.94
                               20100529 |          1        0.01       99.95
                                 201201 |          1        0.01       99.96
                               20120617 |          1        0.01       99.97
                                 201209 |          1        0.01       99.98
                          201209,201512 |          1        0.01       99.99
                                 201307 |          1        0.01      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 19 Apr 2017