by Calculated Risk on 5/27/2010 03:49:00 PM

Most of the revisions in the "Second Estimate" GDP report this morning were small; the headline GDP number was revised down to 3.0% from 3.2% (annualized real growth rate).

There are really two measures of GDP: 1) real GDP, and 2) real Gross Domestic Income (GDI). The BEA also released GDI today. Recent research suggests that GDI is often more accurate than GDP.

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 to date recessions.

The following graph is constructed as a percent of the previous peak in both GDP and GDI. 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%. The recent recession is marked as ending in Q3 2009 - this is preliminary and NOT an NBER determination.

Click on graph for larger image in new window.

It appears that GDP bottomed in Q2 2009 and GDI in Q3 2009. Real GDP is only 1.2% below the pre-recession peak - but real GDI is still 2.3% below the previous peak.

GDI suggests the recovery has been more sluggish than the headline GDP report and better explains the weakness in the labor market.

Also "Personal income excluding current transfer receipts (billions of chained 2005 dollars)" was revised down for the last two quarters, and now shows essentially no growth in real personal income since the bottom of the recession.