Charting Halloween

According to the author:
The Graph-O’-Lantern – 6% pie, 5% Venn, 13% bar, and 100% gourd!
The description of each chart, clockwise from the upper-left:

• Typical Witches’ Brew Composition By Weight (pie chart)
  
• Known Scare Tactics Of Ghosts And Zombies (Venn diagram)
  
• Vampire-Related Deaths Per Decade, Transylvania, 1960-2009 (bar graph)