Frequencies for first 10,000 rows of importdate variable in bencs2018 dataset :

        Import Date |      Freq.     Percent        Cum.
--------------------+-----------------------------------
2017-05-25 02:20:18 |          9        0.09        0.09
2017-08-08 02:20:26 |        428        4.28        4.37
2017-08-15 02:20:31 |         54        0.54        4.91
2017-09-02 02:21:27 |      3,752       37.52       42.43
2017-09-22 02:20:26 |      2,957       29.57       72.00
2017-09-26 02:21:16 |        243        2.43       74.43
2017-11-01 02:20:20 |      2,557       25.57      100.00
--------------------+-----------------------------------
              Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 8 Dec 2017