Frequencies for first 10,000 rows of refothph variable in nhamcsopd1996 dataset : refer to | other | physician/c | linic | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,372 93.72 93.72 1 | 628 6.28 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016