Frequencies for first 10,000 rows of gestimp variable in natl2001 dataset : Gestation | Imputation | Flag | Freq. Percent Cum. ------------+----------------------------------- 1 | 914 9.14 9.14 . | 9,086 90.86 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015