Frequencies for first 10,000 rows of bloodalc variable in nhamcsed1998 dataset : blood | alcohol | concentrati | on | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,702 97.02 97.02 1 | 298 2.98 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016