A Note on Economic Stimulus, GDP Growth, and Politics

Via Calculated Risk, here’s what Council of Economic Advisors Chair Christina Romer had to say last week in testimony before the Joint Economic Committee about how the stimulus has and will impact growth in the near term:

In a report issued on September 10, the Council of Economic Advisers (CEA) provided estimates of the impact of the ARRA on GDP and employment. ...

These estimates suggest that the ARRA added two to three percentage points to real GDP growth in the second quarter and three to four percentage points to growth in the third quarter. This implies that much of the moderation of the decline in GDP growth in the second quarter and the anticipated rise in the third quarter is directly attributable to the ARRA.

Fiscal stimulus has its greatest impact on growth around the quarters when it is increasing most strongly. When spending and tax cuts reach their maximum and level off, the contribution to growth returns to roughly zero. This does not mean that stimulus is no longer having an effect. Rather, it means that the effect is to keep GDP above the level it would be at in the absence of stimulus, not to raise growth further. Most analysts predict that the fiscal stimulus will have its greatest impact on growth in the second and third quarters of 2009. By mid-2010, fiscal stimulus will likely be contributing little to growth.

In layman’s terms, when first comes online, it adds GDP growth that wouldn’t have otherwise occurred. Then, after a time, it props the economy up at a level it wouldn’t have otherwise seen. (Romer says we’ve seen the first part, and are about to see the second part.) Here’s the thing, when the economy isn’t growing on its own but is being propped up at a higher level than it otherwise would have been due to stimulus, GDP growth will sit at basically zero. That doesn’t mean the stimulus isn’t working – the economy is producing more than it otherwise would have. 

This also means that the stimulus going offline is a “drag” - or has a negative effect - on growth as that government spending is no longer in the economy. What it doesn’t mean as that it’s making the economy worse, and it’s worth inoculating against that misunderstanding of the GDP data that will inevitably arise. Rather, it will have as measurable a positive effect on the economy in the short term and will jumpstart sustained growth (at what level is still an open question). And the investments in the elements of sustained growth – infrastructure, smart grid, energy, education, R%D, etc – will continue to pay off for many years to come.