Frequencies for first 10,000 rows of econds_2 variable in linkco1991us_num dataset :

Sequence of |
  condition |
     within |
part/line 2 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      3,012       30.12       30.12
          1 |      6,191       61.91       92.03
          2 |        797        7.97      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015