Frequencies for first 10,000 rows of cstratm variable in nhamcsed2011 dataset :

  Clustered |
 CSTRATM -- |
     masked |      Freq.     Percent        Cum.
------------+-----------------------------------
   2.01e+07 |      3,782       37.82       37.82
   2.02e+07 |      1,599       15.99       53.81
   4.01e+07 |      2,627       26.27       80.08
   4.02e+07 |      1,992       19.92      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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