Frequencies for first 10,000 rows of quarter variable in sdued2005 dataset :

    Quarter |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      7,325       73.25       73.25
          2 |      2,675       26.75      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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