Frequencies for first 10,000 rows of quarterbegindate variable in sdued1997 dataset :

    Quarter |
 Begin Date |      Freq.     Percent        Cum.
------------+-----------------------------------
 01/01/1997 |      6,243       62.43       62.43
 04/01/1997 |      3,757       37.57      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 12 Feb 2018