Frequencies for first 10,000 rows of exp_dt_num variable in drug2010q3 dataset :

 Expiration |
date of the |
      drug. |
 (YYYYMMDD) |      Freq.     Percent        Cum.
------------+-----------------------------------
  31aug2010 |          1        0.01        0.01
  01sep2010 |          1        0.01        0.02
  30sep2010 |          2        0.02        0.04
  31jul2011 |          1        0.01        0.05
  30nov2011 |          1        0.01        0.06
  01feb2012 |          1        0.01        0.07
  30sep2012 |          1        0.01        0.08
  31oct2012 |          1        0.01        0.09
          . |      9,991       99.91      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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