Frequencies for first 10,000 rows of hyaline variable in linkco1991us_num dataset :

    Hyaline |
   membrane |
    disease |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        410        4.10        4.10
          2 |      8,448       84.48       88.58
          9 |      1,142       11.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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