Frequencies for first 10,000 rows of f_api variable in natlterr2005 dataset : API codes U | Freq. Percent Cum. ------------+----------------------------------- 0 | 6,266 62.66 62.66 1 | 3,734 37.34 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015