The three articles which comprise this section focus on U.S. real gross domestic product. Each takes a unique approach. Bracken's forecast is based on past government spending, and extends to 2003. Roper and Gary base their forecast on consumption spending and population; using census projections, they are able to forecast to 2010. Mulligan forecasts GDP to 2000 based on projected real investment expenditures.
Bracken's two-year forecast of GDP is based on past government spending. Using the Keynesian aggregate expenditures multiplier, she predicts a brief recession in 2001 and a longer one in 2003, provided aggregate expenditures fail to keep pace with long-term GDP growth.
Roper and Gary employ a modified inverted consumption function, augmented with population, to project real GDP and per-capita real GDP ten years into the future, to 2010. They predict annual growth of both output and consumption to be between one and two percent per year for the next ten years, but most positively, predict per-capita GDP will increase by approximately one percent per year for the next ten years, due to steady population growth.
Mulligan uses a Keynesian aggregate expenditures model to predict investment spending will rise 14% throughout 1999 and 13% throughout 2000. Real GDP is projected to increase 3.2% in 1999 and 2.9% in 2000.
Taken together, these three forecasts agree in only one way: each points to the paramount importance of maintaining aggregate expenditures. Bracken, who's model is driven by government spending, predicts a recession if aggregate expenditures do not continue to grow at a rate sufficient to support current GDP growth. Roper and Debrell, who's model is driven by consumption, and Mulligan, who's model is driven by investment, predict rosy economic growth, provided aggregate expenditures continue to grow at appropriate rates.