by Calculated Risk on 4/12/2010 11:59:00 AM

Calling the beginning or end of a recession takes time. The National Bureau of Economic Research (NBER) waits until the data is revised, and if the recovery is sluggish, this process can take from 18 months to two years or longer.

In addition, if the economy slides into recession again, the committee will only consider it a new recession if most major indicators were close to or above their previous highs. Otherwise it will just be considered a continuation of the previous recession.

A good example of the NBER calling two separate recessions was in the early '80s, from the NBER memo:

"The period following July 1980 will appear in the NBER chronology as an expansion. An important factor influencing that decision is that most major indicators, including real GNP, are already close to or above their previous highs."
emphasis added

It will take some time for most major indicators to be above their previous high after the "great recession" because of the severe contraction as the graphs below show.

GDP is the key measure, as the NBER committee notes in their business cycle dating procedure:

The committee views real GDP as the single best measure of aggregate economic activity.

This is actually two measures: 1) real GDP, and 2) real Gross Domestic Income (GDI). For a discussion on GDI, see from Fed economist Jeremy Nalewaik, “Income and Product Side Estimates of US Output Growth,” Brookings Papers on Economic Activity. An excerpt:

The U.S. produces two conceptually identical official measures of its economic output, currently called Gross Domestic Product (GDP) and Gross Domestic Income (GDI). These two measures have shown markedly different business cycle fluctuations over the past twenty five years, with GDI showing a more-pronounced cycle than GDP. These differences have become particularly glaring over the latest cyclical downturn, which appears considerably worse along several dimensions when looking at GDI. ...

In discussing the information content of these two sets of estimates, the confusion often starts with the nomenclature. GDP can mean either the true output variable of interest, or an estimate of that output variable based on the expenditure approach. Since these are two very different things, using “GDP” for both is confusing. Furthermore, since GDI has a different name than GDP, it may not be initially clear that GDI measures the same concept as GDP, using the equally valid income approach.

The NBER uses both real GDP and real GDI.

Note: The following graphs are all constructed as a percent of the peak in each indicator. This shows when the indicator has bottomed - and when the indicator has returned to the level of the previous peak. If the indicator is at a new peak, the value is 100%. On all graphs the recent recession is marked as ending in July 2009 or Q3 2009 - this is preliminary and NOT an NBER determination. GDP is quarterly, the other data is monthly.

The first graph is for GDP and GDI:

Click on graph for larger image in new window.

It appears that GDP bottomed in Q2 2009 and GDI in Q3 2009. This is the key measure, and the NBER will probably use GDP and GDI to determine the trough of the recession. Real GDP is only 2.0% below the pre-recession peak - and real GDP 2.7% below the previous peak - so both could be at new highs later this year or early in 2011, even with a sluggish recovery.

The second graph is for monthly industrial production based on data from the Federal Reserve.

Industrial production bottomed in June 2009. The NBER will consider this measure when trying to identify the month the recession ended. Note that industrial production is still substantially below the pre-recession levels - so it might be some time before this measure is at or above earlier levels.

Now for some less optimistic measures the NBER uses ...

The third graph is for employment. It appears the employment recession might have bottomed in February, but it will take a long time before this measure is at pre-recession levels.

Historically employment was a coincident indicator for the end of recessions, but that hasn't been true for the previous two recessions (1990-1991 and 2001) and also will not be true for the "great recession" if the NBER determines an end date in July 2009.

If the NBER waits for employment to return to pre-recession levels, we might be waiting for an annoucement for a long time.

And the last graph is for real personal income excluding transfer payments. This bottomed in Sept 2009, but has moved sideways since then. This shows the effect of the stimulus programs that boosted GDP and income - but not income less transfer payments.

This will be a key measure of a sustainable recovery, and once again it will take a long time to return to pre-recession levels.

These graphs are useful in trying to identify peaks and troughs in economic activity. My guess is the economy bottomed by most measure in Q3 2009 (probably July), but I don't expect an announcement from the NBER until the end of 2010 at the earliest - and perhaps well into 2011 or beyond.