Some player data 1996-2017 by Sean Lahman, licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
Some player data 2017 by Chadwick Baseball Bureau, licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
Hall of Fame ballot data from 2013-2017 courtesy of The Baseball Hall of Fame Tracker by Ryan Thibodaux.
All Hall of Fame ballot data from 2009-2012 courtesy of The Baseball Hall of Fame Tracker via @leokitty.
Cy Young, MVP, Rookie of the Year and Manager of the Year ballot data compiled by Jeff Fletcher for the BBWAA.