Frequencies for first 10,000 rows of tkduty_t variable in vindecode dataset : (duty type) | medium | description | . | Freq. Percent Cum. ------------+----------------------------------- | 5,924 59.24 59.24 Heavy Duty | 532 5.32 64.56 Light Duty | 2 0.02 64.58 Medium Duty | 2,102 21.02 85.60 Unknown | 1,440 14.40 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Oct 2016