Frequencies for classification variable in enfrep20180404 dataset :

    Classification |      Freq.     Percent        Cum.
-------------------+-----------------------------------
           Class I |          7        4.61        4.61
          Class II |        130       85.53       90.13
         Class III |         10        6.58       96.71
Not Yet Classified |          5        3.29      100.00
-------------------+-----------------------------------
             Total |        152      100.00

by Jean Roth , jroth@nber.org , 6 Apr 2018