Frequencies for first 10,000 rows of popprovm variable in namcs2002 dataset :

Estimated # |
 of inscope |
prov in PSU |
   (masked) |      Freq.     Percent        Cum.
------------+-----------------------------------
         -1 |      4,441       44.41       44.41
          0 |      5,559       55.59      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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