Frequencies for first 10,000 rows of rf_inftr variable in natlterr2014 dataset 

Infertility |
  Treatment |
 Used Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,077       10.77       10.77
          N |      8,831       88.31       99.08
          U |         76        0.76       99.84
          Y |         16        0.16      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016