Actually, the real statistic is that just about 15% of all people who smoke exhibit any forms of disease associated with it (i.e. cancer). It all depends on how your body is able to metabolize the carcinogens or other toxic chemicals that come into direct contact with your lungs. The negative adds on smoking are only partially true. But live and let live, let people do what they want.
Huh???
http://www.cdc.gov/tobacco/data_statistics/fact_sheets/health_effects/effects_cig_smoking/