Frequencies for first 10,000 rows of ld_ster variable in natlterr2012 dataset :

   Steroids |
        RFP |
611=f_ld_st |
   eroids R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,163       11.63       11.63
          N |      8,352       83.52       95.15
          U |        349        3.49       98.64
          Y |        136        1.36      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 5 May 2016