Frequencies for first 10,000 rows of eformulaer variable in nhamcsed2014 dataset :

     Recode of EFORMULAE for |
 trending with data prior to |
                        2010 |      Freq.     Percent        Cum.
-----------------------------+-----------------------------------
                     Unknown |      1,580       15.80       15.80
              Not applicable |      1,638       16.38       32.18
                         Yes |      6,624       66.24       98.42
                          No |        158        1.58      100.00
-----------------------------+-----------------------------------
                       Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 11 Apr 2017