Ow do unemployment, under-employment and discouraged workers affect GDP in an economy?

** Writing Assignment (see requirements below)**
The 2007-2008 World Financial crisis generated a Global Economic Recession described by economists as second to the 1930s Great Depression. Like most economies, the U. S. economy experienced a huge economic downturn; its number of unemployed reached historic highs. The International Monetary Fund global macroeconomic prospects for 2014 forecast a a?bumpya? recoverya? and a?low GDPa? growth rates for
For most of us, economic recovery and our economic well-being are measured through the prism of our income levels. Minimal to zero income is associated with unemployment, under-employment and discouraged workers.
Title: How do unemployment, under-employment and discouraged workers affect GDP in an economy?
Paper Requirements:
i?? Minimum of Four pages (top to bottom), double spaced, neatly typed.
i?? Attach an additional page for bibliography/work cited
i?? Include introduction and conclusion; NO Wikipedia please!