Frequencies for first 10,000 rows of popprovm variable in nhamcsed1996 dataset :

estimated # |
 of inscope |
  providers |
     in psu |
   (masked) |      Freq.     Percent        Cum.
------------+-----------------------------------
        297 |      2,055       20.55       20.55
        306 |      2,596       25.96       46.51
        321 |      2,982       29.82       76.33
        368 |      2,367       23.67      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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