Frequencies for first 10,000 rows of chas_tr variable in vehicle dataset : VIN | Chassis-Tru | ck | Freq. Percent Cum. ------------+----------------------------------- 99 | 1,830 18.30 18.30 . | 8,170 81.70 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Apr 2016