Frequencies for first 10,000 rows of prescr4 variable in nhamcsed2009 dataset :

   for rx4, |
prescriptio |
   n status |
       code |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,160       11.60       11.60
          2 |         83        0.83       12.43
          3 |         13        0.13       12.56
          5 |        278        2.78       15.34
          . |      8,466       84.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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