Interesting. It seems that only Truman's debt-cutting is responsible for 'outweighing' Obama's dramatic increase in the debt (relative to GDP). Even Reagan and Clinton increased debt relative to GDP.
That being said, this definitely over-represents the increase in debt when a president increases the absolute debt while the economy shrinks/stagnates, and vice versa.
My understanding of the recent debt is that it is caused less by increased spending and more by a dramatic drop in revenue because of the economic collapse since 2008.
Eyeballing the chart, it looks like the debt change was following its own function irrespective of the president.
The ordering is not chronological.
Pretty sickening. 90% top tax rate though - that's pretty ridiculous.