Frequencies for first 10,000 rows of importdate variable in bencs2015 dataset :

     Import Date |      Freq.     Percent        Cum.
-----------------+-----------------------------------
 1/16/2015 17:32 |        183        1.83        1.83
 10/2/2014 12:25 |        216        2.16        3.99
 5/20/2015 14:11 |      7,050       70.50       74.49
  8/27/2014 3:27 |        108        1.08       75.57
  8/28/2014 4:23 |         72        0.72       76.29
   8/3/2014 8:59 |         18        0.18       76.47
  8/5/2014 13:28 |          5        0.05       76.52
   8/6/2014 8:27 |         50        0.50       77.02
   9/3/2014 4:28 |        126        1.26       78.28
   9/4/2014 3:25 |         80        0.80       79.08
   9/5/2014 3:32 |         36        0.36       79.44
   9/6/2014 3:39 |      2,056       20.56      100.00
-----------------+-----------------------------------
           Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 9 Dec 2017