Frequencies for first 10,000 rows of uld_febr variable in natl2003 dataset :

  Febrile U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        160        1.60        1.60
          2 |      8,998       89.98       91.58
          8 |          7        0.07       91.65
          9 |        835        8.35      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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