For some one looking for statistical data about USA, the labyrinth of different sources of official data can be disturbing.
For instance, let’s try to find GDP, current prices, 2009 and its structure by industry.
US Census Bureau provides a table in the Statistical Abstract (here
for 2012 edition, see table 670, released last September 2011): 2009
GDP is 14119 b.USD and manufacturing contributes with 1585 (11.2%). All
industries is private industries minus agriculture, forestry, fishing
and hunting: 12063, which means manufacturing is 13.1% of all industries
value added. “All industries” appears often, specially in US Census
data, and it means all sectors of the economy unless “agriculture,
forestry, fishing, hunting”, and all government services and activities.
According to previous data, “all industries” is the non farm private
sector of the economy, and it means 89% of the economy. The remaining
11% are basically government: farm related business (agriculture,
forestry, fishing, hunting) only contribute with 1%.
When we compare it with the estimates of 2009 ASM Annual Survey of Manufactures (here, see
“Statistics for Industry groups and industries”), we get very different
numbers per industry. From the estimates of each industry,
manufacturing value added should have been 1976, a 26% higher estimate
than the previous one (1585). Important differences per industry can be
found when comparing table 670 (2009) with 2009 ASM estimates for value
added per industry.
But BEA Bureau of Economic Analysis source about industry economic accounts (here)
gives different numbers: 2009 GDP was 13939, manufacturing value added
was 1540 (11% GDP) and all industries should have been 11878
(manufacturing = 13%). Detail per industry is available and can be
compared with the previous two sources.
can also have a look at the 2011 Economic Report of the President
(table B-12). GDP for 2009 was 14119, manufacturing 1549 and all
industries 12063. The same values of US Census Bureau.
What if we look for an outside source? OECD Stat.Extracts
for instance. USA GDP was 14119 in 2009 (the same as US Census), and
manufacturing value added was 1733 (12.2% GDP, a different value from US
Census). From OECD data we estimate “all industries” by GDP minus farm
business minus government: 10349 (to be confirmed). GDP numbers are also available from IMF World Bank (World Economic Outlook, 2011 edition). For USA, 2009, value is 12703.
table provides the structure of manufacturing added value,
by industries, from 2009 ASM (US Census) and BEA (Annual Industry
Accounts) (b.USD and %):
Confused? Me too …
methodologies, different definitions and the revisions process may
explain the differences.
Macroeconomic data are estimates of an
associated variance (error). Not exact numbers. So differences are not
very relevant and significant. Different estimates tell a similar
“story” in this case. But when comparing between different countries,
industries, … that can be important - the same source must be used to
guarantee homogeneity of data criteria.
(Update, 1 April: a good guide to these issues is available from BEA: "A guide to national income and product accounts of the United States")