Frequencies for first 10,000 rows of ip_hepatc variable in natl2017 dataset :

Hepatitis C |
      Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,808       98.08       98.08
          U |        107        1.07       99.15
          Y |         85        0.85      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 19 Sep 2018