Frequencies for first 10,000 rows of f_urf_eclamp variable in natl2007 dataset : Eclampsia | (urf_eclam) | U;R | Freq. Percent Cum. ------------+----------------------------------- 0 | 4 0.04 0.04 1 | 9,996 99.96 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015