Frequencies for first 10,000 rows of ld_ster variable in natlterr2009 dataset :

   Steroids |
        RFP |
611=f_ld_st |
   eroids R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,449       24.49       24.49
          N |      7,315       73.15       97.64
          U |          2        0.02       97.66
          Y |        234        2.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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