Frequencies for first 10,000 rows of thorc_srgry_sw variable in pos2010 dataset : SPEC: | THORACIC | Freq. Percent Cum. ------------+----------------------------------- | 9,632 96.32 96.32 N | 358 3.58 99.90 Y | 10 0.10 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 17 May 2017