The real problem: Private Investment

Want to know the real cause of low GDP growth? Look no further than Private Investment.

Private Investment over Nominal GDP

Private Investment ran with peaks around 10 percent of GDP and troughs around 4 percent throughout the 1960s, 70s and most of the 80s. Since then Private Investment has declined to the point that the latest peak is close to 4 percent.

It is highly unlikely that the US will be able to sustain GDP growth if the rate of investment continues to decline. GDP growth is a factor of population growth and productivity growth. Productivity growth is not primarily caused by people working harder but by working more efficiently, with better tools and equipment. Using an earthmover rather than a wheelbarrow and shovel for example. Falling investment means fewer new tools and efficiencies.

Private Investment & Debt over Nominal GDP

The second graph plots the annual increase in private debt against GDP. You would think that this figure would fall — in line with falling rates of investment. Quite the opposite. Private debt growth is rising. While annual debt growth is nowhere near the red flag of 5 percent of GDP, if it crosses above the rate of private investment — as in 2006 to 2009 — I would consider that a harbinger of another crash.