Deficits = Revenue - Expenditures. It is not just spending that counts, if revenues decrease, like they dramatically did, that accounts for most of the other 80.5%.
Let's compare actual Govt revenues:
2000 2025.2
2001 1991.2
2002 1853.2
2003 1782.3
2004 1880.1
With what they would have been had revenues kept up with GDP growth. GDP growth:
GDP 2000 9817.0 5.9%
2001 10128.0 3.2%
2002 10469.6 3.4%
2003 10971.2 4.8%
2004 11734.3 7.0%
2005 12378.0 5.5%
Revenues if they grew at the same % as GDP:
2000 2025.2
2001 2089.4
2002 2159.8
2003 2263.3
2004 2420.7
Now, compare actual Govt Revenues with Revenues had they kept up with GDP; the last figure is the difference.
2001 1991.2 2089.4 98.2
2002 1853.2 2159.8 306.6
2003 1782.3 2263.3 481.0
2004 1880.1 2420.7 540.6
The total cumualative difference FY2000-2004 is $1,426.4B
Compare that to the increase in total debt:
Total Debt:
http://www.publicdebt.treas.gov/opd/opdpenny.htm
09/30/2004 $7,379,052,696,330.32
09/29/2000 $5,674,178,209,886.86
Total debt increase FY2000-FY2004: $1,705B.
Total loss of tax revenue: $1426B.
Tax revenue loss is 83% of total debt increase.
There's your answer.