Frequencies for first 10,000 rows of rf_artec variable in natl2013 dataset :

      Asst. |
Reproductiv |
          e |
 Technology |
        RFP |
592=f_rf_ce |
      sar R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |         59        0.59        0.59
          U |        167        1.67        2.26
          X |      9,747       97.47       99.73
          Y |         27        0.27      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015