Frequencies for first 10,000 rows of prov1370 variable in pos1993 dataset : tech super | - | radiobioass | ay | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,972 99.72 99.72 1 | 28 0.28 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 26 Jan 2016