Thu Nov 29th, 2012 at 05:38:35 AM EST
From The Federal Reserve Bank of San Francisco Economic Letter #2012-35 of November 26, 2012:
(Cascading Hat Tips to Migeru Shimbun and Economist's View)
Highway Grants: Roads to Prosperity?
By Sylvain Leduc and Daniel Wilson
Federal highway grants to states appear to boost economic activity in the short and medium term. The short-term effects appear to be due largely to increases in aggregate demand. Medium-term effects apparently reflect the increased productive capacity brought by improved roads. Overall, each dollar of federal highway grants received by a state raises that state's annual economic output by at least two dollars, a relatively large multiplier.
Increasing government spending during periods of economic weakness to offset slower private-sector spending has long been an important policy tool. In particular, during the recent recession and slow recovery, federal officials put in place fiscal measures, including increased government spending, to boost economic growth and lower unemployment. One form of government spending that has received a lot of attention is public investment in infrastructure projects. The 2009 American Recovery and Reinvestment Act (ARRA) allocated $40 billion to the Department of Transportation for spending on the nation's roads and other public infrastructure. Such public infrastructure investment harks back to the Great Depression, when programs such as the Works Progress Administration and the Tennessee Valley Authority were inaugurated.
One criticism of public infrastructure programs is that they take a long time to put in place and therefore are unlikely to be effective quickly enough to alleviate economic downturns. The fact is, though, that surprisingly little empirical information is available about the effect of public infrastructure investment on economic activity over the short and medium term.
This Economic Letter examines new research (Leduc and Wilson, forthcoming) on the dynamic effects of public investment in roads and highways on gross state product (GSP), the total economic output of a state. This research focuses on investment in roads and highways in part because it is the largest component of public infrastructure in the United States. Moreover, the procedures by which federal highway grants are distributed to states help us identify more precisely how transportation spending affects economic activity.
We find that unanticipated increases in highway spending have positive but temporary effects on GSP, both in the short and medium run. The short-run effect is consistent with a traditional Keynesian channel in which output increases because of a rise in aggregate demand, combined with slow-to-adjust prices. In contrast, the positive response of GSP over the medium run is in line with a supply-side effect due to an increase in the economy's productive capacity.
We also assess how much bang each additional buck of highway spending creates by calculating the multiplier, that is, the magnitude of the effect of each dollar of infrastructure spending on economic activity. We find that the multiplier is at least two. In other words, for each dollar of federal highway grants received by a state, that state's GSP rises by at least two dollars.
The methodology they employ and the reasoning behind it is of note:
We study forecast revisions rather than changes in actual highway spending for two reasons. First, actual spending may both affect and be affected by current economic conditions, making it difficult to sort out the true causal effects of the spending.
Second, changes in actual spending are most likely to be anticipated years in advance. For that reason, some of their economic effects may be felt before the spending changes actually take place. For instance, a state government and other important players, such as construction and engineering firms, may decide to spend more today if they expect the state to receive more highway grants in the future. In this way, changes in expectations regarding future grants to the states may be important for current economic activity. Failing to account for changes in expectations may lead to incorrect conclusions about how government spending affects economic activity (see Ramey 2011a).
Average response of state GDPs to unexpected grants
In our analysis of how changes in forecasts of highway grants to the states affect state GSP, we control for lags in state GSP, lags in receipt of highway grants, average state GSP levels, and national movements of gross domestic product (GDP) over the sample period from 1990 to 2010.
In Figure 1, the solid line shows the average percentage change in a state's GSP following a 1% increase in forecasted future highway grants to the states. The shaded area around the line represents a 90% probability range. The horizontal axis indicates the number of years after the unanticipated change in forecasted highway grants to the states. The figure shows that changes in the forecasts have a significant short-term effect on state output in the first one to two years. This effect fades, but then increases sharply six to eight years after the forecast revisions, before declining again. This pattern holds up well with alternative estimation techniques, the inclusion of different control variables, and with different data samples.
The forthcoming formal paper will undoubtedly employ much more mathematics and statistics and likely be suitably less readable by mere mortals.
Spending on wind power generation, associated distribution and on upgraded, electrified rail transport powered by same should have a multiplier of at least three.