Frequencies for first 10,000 rows of rn variable in namcs1997 dataset : registered | nurse seen | Freq. Percent Cum. ------------+----------------------------------- 0 | 8,580 85.80 85.80 1 | 1,420 14.20 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016