Frequencies for first 10,000 rows of uniqueplandesign variable in plan2015 dataset :

Unique Plan |
     Design |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,558       15.58       15.58
         No |      4,412       44.12       59.70
        Yes |      4,030       40.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 9 Dec 2017