Frequencies for first 10,000 rows of lpn variable in nhamcsed1997 dataset : licensed | practical | nurse seen | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,731 97.31 97.31 1 | 269 2.69 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016