Frequencies for first 10,000 rows of region variable in nhamcsopd2001 dataset : geographic | region | Freq. Percent Cum. ------------+----------------------------------- 1 | 7,139 71.39 71.39 2 | 2,420 24.20 95.59 3 | 441 4.41 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016