To be sure, the investment peak in 2000 was unusually high; still, the nominal share of business fixed investment in GDP, at 10-3/4 percent at the end of 2005, was well below its forty-year average.
Of course, comparisons of these simple ratios and growth rates do not account for other influences on investment in the macroeconomic environment, such as interest rates, the prices of capital goods, or the rate of increase in final spending. However, a more rigorous exercise using a standard model favored by many forecasters yields a similar conclusion.