Looking at the above chart, you can see that "Keynesian" spending "firepower" is continuing to drop. We live in a time where Nobel Prize winners are big disappointments. For instance, Paul Krugman (and fellow Leftists) continue to advocate more and even massive government spending to combat the slack economy. For ordinary citizens without PhDs, it's obvious that something has changed and, as a country, we're not getting any "bang for the buck" from government deficit spending.
Now for more evidence that this trend continues but above the red trend line drawn above. Take a look at the following chart showing vastly diminished returns for government (public) debt creation. For the first quarter of this year, US government debt increases $359 billion for a measly $142 billion in GDP rise. That works out to about $0.30 when you calculate Change in GDP/Change in Debt.
Please, someone stop the madness!