Frequencies for first 10,000 rows of year variable in nadac dataset :

 As of Year |      Freq.     Percent        Cum.
------------+-----------------------------------
       2013 |        283        2.83        2.83
       2014 |      2,873       28.73       31.56
       2015 |      2,435       24.35       55.91
       2016 |      2,197       21.97       77.88
       2017 |      1,910       19.10       96.98
       2018 |        302        3.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 1 Mar 2018