Frequencies for first 10,000 rows of exprmt_rsrch_cndctd_sw variable in pos1993 dataset :

experimenta |
 l research |
  conducted |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      7,622       76.22       76.22
          N |      2,360       23.60       99.82
          Y |         18        0.18      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017