Frequencies for first 10,000 rows of prescr1 variable in nhamcsopd1999 dataset :

prescriptio |
   n status |
   code for |
 medication |
          # |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      4,881       48.81       48.81
          2 |        735        7.35       56.16
          3 |        636        6.36       62.52
          . |      3,748       37.48      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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