Your graph is misleading. And your cherry picking what you base it on. I prefer simple arithmetic.
How about % increase in total debt? (36.56%)
National Debt 02/01/1993 4,176,491,860,224.29 (Clinton Takes Office)
National Debt 02/01/2001 5,703,346,472,448.65 (Bush Takes Office)
Well... this increase in the dept is accpetable as the overall economy improved to such a point that although the nation dept increased, it was becoming a smaller pecentage in reation to america's economy.
oh and by the way...
02/01/2001 - $5,703,346,472,448.65
03/21/2008 - $9,392,558,361,529.10
add the fact that our economy is in a bit of a slowdown (possible understatement)...