Frequencies for first 10,000 rows of ewarn variable in namcs2012 dataset :

 If orders for prescriptions |
   submitted electronically, |
  warnings of drug interacti |      Freq.     Percent        Cum.
-----------------------------+-----------------------------------
                     Unknown |        352        3.52        3.52
              Not applicable |      2,768       27.68       31.20
         Yes, used routinely |      5,979       59.79       90.99
 Yes, but NOT used routinely |        309        3.09       94.08
Yes, but turned off/not used |         16        0.16       94.24
                          No |        576        5.76      100.00
-----------------------------+-----------------------------------
                       Total |     10,000      100.00

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