Frequencies for first 10,000 rows of alcohol variable in nhamcsed2001 dataset :

     is visit related to alcohol use? |      Freq.     Percent        Cum.
--------------------------------------+-----------------------------------
                                Blank |        268        2.68        2.68
                   Yes, patient’s use |        302        3.02        5.70
              Yes, other person’s use |          8        0.08        5.78
                                   No |      8,249       82.49       88.27
                              Unknown |      1,169       11.69       99.96
Both patient`s and other person`s use |          4        0.04      100.00
--------------------------------------+-----------------------------------
                                Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016