Frequencies for first 10,000 rows of ld_ster variable in natlterr2011 dataset :

   Steroids |
        RFP |
611=f_ld_st |
   eroids R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      2,536       25.36       25.36
          N |      6,232       62.32       87.68
          U |      1,092       10.92       98.60
          Y |        140        1.40      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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