Frequencies for year variable in pchsa2003_2007 dataset :

   Year ( ( |
2007 + 2003 |
    ) / 2 ) |      Freq.     Percent        Cum.
------------+-----------------------------------
       2005 |      3,437      100.00      100.00
------------+-----------------------------------
      Total |      3,437      100.00

by Jean Roth , jroth@nber.org , 14 Mar 2018