Frequencies for first 10,000 rows of nursepr variable in namcs1997 dataset : nurse | practitione | r seen | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,910 99.10 99.10 1 | 90 0.90 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016