This slide shows trends in cancer incidence rates for all sites combined from 1975 to 2011. The current cancer incidence rate (averaged during 2007-2011) is 22% lower in women than in men. The reasons for this are not well understood, but likely reflect differences in environmental and hormonal exposures. During the most recent 5 years of data, rates declined slightly in men and were stable in women. The decrease among men is attributed mainly to declines in prostate, lung, and colorectal cancers.