The point of that chart was to show that spending decreased in absolute, not just relative, terms in the 1990's, countering the idea that the trajectory is towards inexorable increase. From 1992 to 2012, real GDP growth slightly outpaced discretionary federal expenditures (63% versus 60%).
Moreover, if you look at the chart on page 30-31 of the PDF in the first link, you can see that non-defense + defense expenditures increased from $761 billion FY2012 dollars in 1977 to ~$1,166 billion in 2012 (adding back ~$123 billion for Iraq and Afghanistan that isn't reflected in that chart),[1] an increase of 53% over 35 years. In that time period, U.S. real GDP grew 152% and the U.S. population grew 43%.
To put it in concrete terms, each person in 1977 bore $3,460 of discretionary expenditures while someone in 2012 bore $3,700 of discretionary expenditures. But in 1977 it was 14.2% per-capita income, while in 2012 it was 8.6% of per-capita income.
[1] Note that 1977 was two years after the end of the Vietnam war.
Moreover, if you look at the chart on page 30-31 of the PDF in the first link, you can see that non-defense + defense expenditures increased from $761 billion FY2012 dollars in 1977 to ~$1,166 billion in 2012 (adding back ~$123 billion for Iraq and Afghanistan that isn't reflected in that chart),[1] an increase of 53% over 35 years. In that time period, U.S. real GDP grew 152% and the U.S. population grew 43%.
To put it in concrete terms, each person in 1977 bore $3,460 of discretionary expenditures while someone in 2012 bore $3,700 of discretionary expenditures. But in 1977 it was 14.2% per-capita income, while in 2012 it was 8.6% of per-capita income.
[1] Note that 1977 was two years after the end of the Vietnam war.