Frequencies for first 10,000 rows of rn variable in nhamcsopd2002 dataset :

    rn seen |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,122       51.22       51.22
          1 |      4,878       48.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016