Frequencies for first 10,000 rows of pain variable in nhamcsed2006 dataset :

 presenting |
   level of |
       pain |      Freq.     Percent        Cum.
------------+-----------------------------------
      blank |        382        3.82        3.82
       none |      1,969       19.69       23.51
       mild |      1,369       13.69       37.20
   moderate |      2,238       22.38       59.58
     severe |      1,978       19.78       79.36
    unknown |      2,064       20.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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