The U.S. Congressional Budget Office (CBO) put together this chart on Federal revenues over the past three years from the largest sources: individual, corporate, and Social Insurance (social security) and other. Federal Revenues by Fiscal Year  (click for chart)

How would you summarize this chart?

When putting the 2009 revenue against expenditures, CBO’s Monthly Budget Review, the federal budget deficit was about tagged at $1.4 trillion in fiscal year 2009, nearly $1 trillion greater than the shortfall recorded in 2008. Relative to the size of the economy, the 2009 deficit was equal to 9.9 percent of GDP (the highest since 1945), compared with 3.2 percent in 2008. Both lower revenues and increased spending contributed to the growth in the deficit. 

What are the causes and consequences of this historic budget deficit?