Frequencies for first 10,000 rows of phyper variable in natlterr2001 dataset : Hypertensio | n - | pregnancy-a | ssociated | Freq. Percent Cum. ------------+----------------------------------- 1 | 339 3.39 3.39 2 | 9,638 96.38 99.77 8 | 20 0.20 99.97 9 | 3 0.03 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Dec 2015