Frequencies for first 10,000 rows of exp_dt_num variable in drug2011q4 dataset :

 Expiration |
date of the |
      drug. |
 (YYYYMMDD) |      Freq.     Percent        Cum.
------------+-----------------------------------
  02sep2012 |          1        0.01        0.01
  05oct2012 |          1        0.01        0.02
  22oct2012 |          2        0.02        0.04
  08nov2012 |          1        0.01        0.05
  15nov2012 |          1        0.01        0.06
  29nov2012 |          2        0.02        0.08
  31mar2013 |          1        0.01        0.09
  15apr2013 |          1        0.01        0.10
  01oct2013 |          1        0.01        0.11
          . |      9,989       99.89      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Dec 2015