Frequencies for first 10,000 rows of quarter variable in sdued1998 dataset :

    Quarter |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      6,581       65.81       65.81
          2 |      3,419       34.19      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Feb 2018