Frequencies for first 10,000 rows of prov2615 variable in pos1995 dataset :

   calendar |
  year test |
     volume |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,494       94.94       94.94
         90 |        272        2.72       97.66
         91 |        234        2.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016