Frequencies for first 10,000 rows of stratm variable in namcs1994 dataset :

psu stratum |
     marker |
   (masked) |      Freq.     Percent        Cum.
------------+-----------------------------------
        201 |      1,437       14.37       14.37
        202 |      1,521       15.21       29.58
        203 |        984        9.84       39.42
        204 |        906        9.06       48.48
        401 |      1,151       11.51       59.99
        402 |      1,572       15.72       75.71
        403 |      1,544       15.44       91.15
        404 |        885        8.85      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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