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

PSU stratum |
     marker |
   (masked) |      Freq.     Percent        Cum.
------------+-----------------------------------
        201 |      1,375       13.75       13.75
        202 |      1,020       10.20       23.95
        203 |        664        6.64       30.59
        204 |      1,382       13.82       44.41
        401 |        648        6.48       50.89
        402 |      1,265       12.65       63.54
        403 |      2,658       26.58       90.12
        404 |        988        9.88      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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