https://www.cdc.gov/nchs/data/health_policy/influenza-and-pneumonia-deaths-2008-2015.pdf
NOTES: Data presented in this table are based on all complete death records received and processed by the Centers for Disease Control and Prevention’s National Center for Health Statistics (NCHS) as of March 17, 2016. Data for 2008 through 2014 are final data, while 2015 data are provisional..... Influenza season is defined as early October through mid-May.