Frequencies for first 10,000 rows of cpr variable in nhamcsed1993 dataset :

        cpr |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,979       99.79       99.79
          1 |         21        0.21      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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