19. The non-transitory computer-readable medium of claim 15 , wherein the method further comprises storing contents of the markup document in footnotes, wherein the footnotes are viewable in a footnote view.
19. The non-transitory computer-readable medium of claim 15 , wherein the method further comprises storing contents of the markup document in footnotes, wherein the footnotes are viewable in a footnote view. 20. The non-transitory computer-readable medium of claim 19 , wherein the method further comprises modifying the footnotes in response to corresponding modifications to the chart view.