Frequencies for first 10,000 rows of cpr variable in nhamcsed2012 dataset :

        CPR |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,990       99.90       99.90
        Yes |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016