diagrammatical vs graphical

diagrammatical

adj
  • diagrammatic 

graphical

adj
  • Of, related to, or using graphics. 

  • Written or engraved; formed of letters or lines. 

  • Of, related to, or shown on a graph. 

How often have the words diagrammatical and graphical occurred in a corpus of books? (source: Google Ngram Viewer )