Frequencies for drugres2 variable in person dataset : DRUG TEST | RESULTS-2 | Freq. Percent Cum. ------------+----------------------------------- 0 | 1,065 98.89 98.89 177 | 7 0.65 99.54 187 | 2 0.19 99.72 407 | 1 0.09 99.81 695 | 2 0.19 100.00 ------------+----------------------------------- Total | 1,077 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016