Frequencies for measurestartdatestr variable in hqi_national_hai dataset :

    Measure |
 Start Date |      Freq.     Percent        Cum.
------------+-----------------------------------
 01/01/2015 |          2       25.00       25.00
 07/01/2014 |          6       75.00      100.00
------------+-----------------------------------
      Total |          8      100.00

by Jean Roth , jroth@nber.org , 15 Nov 2016