Frequencies for first 10,000 rows of gestimp variable in natl1994 dataset : Gestation | Imputation | Flag | Freq. Percent Cum. ------------+----------------------------------- 1 | 1,400 14.00 14.00 . | 8,600 86.00 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015