macro topics nick bloom heterogeneity and reallocation
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MACRO TOPICS Nick Bloom Heterogeneity and Reallocation. Big Overview. Economists started looking at establishment data in the 1990s (Haltiwanger, Davis, Bartelsman, Bailey etc.) There was surprise over: High levels of turnover Heterogeneity within industries - PowerPoint PPT PresentationTRANSCRIPT
Nick Bloom, Macro Topics, Spring 2009
MACRO TOPICS
Nick Bloom
Heterogeneity and Reallocation
Nick Bloom, Macro Topics, Spring 2009
Big Overview
Economists started looking at establishment data in the 1990s (Haltiwanger, Davis, Bartelsman, Bailey etc.)
There was surprise over:
• High levels of turnover
• Heterogeneity within industries
• The lumpiness of micro-economic activity
• The importance of reallocation in driving productivity
Nick Bloom, Macro Topics, Spring 2009
Why should you be interested in this?
First, this is important to understanding macroeconomic activity – e.g. 3/4 productivity growth is reallocation, unemployment driven by rates of churn
Second, “micro to macro” is a fertile area of research:• It is new – many open questions• It is hard – typically needs mix of empirics, simulation
and modeling, so barriers to entry high
Third, the NBER has a Census node. Census data is painful to access, but this also deters – so still low-hanging fruit
Nick Bloom, Macro Topics, Spring 2009
High levels of turnover
Heterogeneity within industries
The lumpiness of micro-economic activity
The importance of reallocation in driving productivity
Nick Bloom, Macro Topics, Spring 2009
Turnover
About 15% of jobs are destroyed and 20% created in the private sector every year. About 80% of this turnover occurs within the same SIC-4 digit industry
This is robust across countries (US, Europe, Asia and SA)
But, before I show data a couple of point on definitions:
• This is turnover in “jobs”, defined in terms of establishment employment changes, e.g. CES
• A linked (but distinct concept) is turnover in “employment” – which is two to three times higher – defined in terms of workers changes, e.g. CPS
Nick Bloom, Macro Topics, Spring 2009
Turnover in “Jobs” versus “Employment” – Expanding Firm example
Source: John Haltiwanger Note: Worker flow=14, Job flow=4
Nick Bloom, Macro Topics, Spring 2009Source: John Haltiwanger
Turnover in “Jobs” versus “Employment” – Contracting Firm example
Note: Worker flow=15, Job flow=9
Nick Bloom, Macro Topics, Spring 2009
Quarterly Job Flows in Private Sector, 1990-2005, BED data
Source: John Haltiwanger
(1) Net jobs flows equal change in employment ≈ change in unemployment(2) Gross flows are much bigger than net flows(3) Reduction in job churn that (in manufacturing) part of a longer trend)(4) Job destruction does not necessarily mean firing – could be not hiring a replacement for a separation.
Nick Bloom, Macro Topics, Spring 2009
JOLTS monthly worker turnover data
Source: John Haltiwanger
Depth of post 9/11 recession: 1) Figures don’t add up (JOLTS is not good for
employment – CES survey more accurate)2) Still massive churn – including quits – in depths of
the recession (I quit a job in December 2001)
Nick Bloom, Macro Topics, Spring 2009
Job Flows and Employment Flows, total private
Source: John Haltiwanger
Nick Bloom, Macro Topics, Spring 2009
Much of the turnover is creation/destruction in same SIC4 industry
Source: John Haltiwanger, Changes defines as % over average base & end years
Excess reallocation = |job creation| + |job destruction| - |job creation-job destruction|
Nick Bloom, Macro Topics, Spring 2009
This is very much in the spirit of Schumpeter
A job-market tip from Schumpeter: the gentleman's handkerchief - very much in fashion right now…
Nick Bloom, Macro Topics, Spring 2009
This is very much in the spirit of Schumpeter
Although probably his most famous quote was:“Early in life I had three ambitions. I wanted to be the greatest economist in the world, the greatest horseman in Austria, and the best lover in Vienna. Well, I never became the greatest horseman in Austria“
To which the (un-attributed) response was:“Those we knew Schumpeter as an Economist, Lover or a Horseman presumed his skills were in the other two fields”
“The fundamental impulse that keeps the capital engine in motion comes from the new consumers’ goods, the new methods of production and transportation, the new markets... [The process] incessantly revolutionizes from within, incessantly destroying the old one, incessantly creating a new one. This process of Creative Destruction is the essential fact of capitalism.”Schumpeter (p. 83, 1942)
Nick Bloom, Macro Topics, Spring 2009
High levels of turnover
Heterogeneity within industries
The lumpiness of micro-economic activity
The importance of reallocation in driving productivity
Nick Bloom, Macro Topics, Spring 2009
Heterogeneity basic facts
Within industries: Only about 10% of cross-establishment spread in output, employment, capital and productivity growth is explained by SIC 4-digit controls
Large: Typical gap between 10th and 90th percentiles of productivity within same 4-digit SIC industry is 50%
Persistent:• About 70% to 80% annual job-flows are persistent• About 60% to 70% annual productivity growth is
persistent
Nick Bloom, Macro Topics, Spring 2009
What could cause this heterogeneity?
One possibility is pure measurement error, but:• Productivity is strongly linked with exit and growth• Spreads are persistent & inter-linked across measures
Several possible economic models of the spread are:• Learning (e.g. Jovanovic, 1982 Econometrica)• Uncertainty and adjustment costs (Dixit and Pindyck, 1994
book; Abel and Eberly 1996 REStud)• Omitted factors - knowledge, vintages, skills etc…• Or even management (eg Bloom & Van Reenen, 2007 QJE)
Still a very active literature trying to explain micro productivity,with only about 10%-20% of variation explained.
Nick Bloom, Macro Topics, Spring 2009
High levels of turnover
Heterogeneity within industries
The lumpiness of micro-economic activity
The importance of reallocation in driving productivity
Nick Bloom, Macro Topics, Spring 2009
Lumpiness of growth
The share of employment growth generated by large adjustments is big (Davis and Haltiwanger, 1992 QJE)
• More than 2/3 manufacturing job creation/destruction accounted for by +25% changes
• For non-manufacturing even greater
Same is true, but more extreme, for investment (Doms and Dunne, 1998 RED).
Suggests substantial adjustment-costs in factor changes
Nick Bloom, Macro Topics, Spring 2009
Lumpiness of employment growth
Source: John Haltiwanger, annual data manufacturing
Nick Bloom, Macro Topics, Spring 2009
High levels of turnover
Heterogeneity within industries
The lumpiness of micro-economic activity
The importance of reallocation in driving productivity
Nick Bloom, Macro Topics, Spring 2009
Re-allocation
Recent studies highlight role of reallocation for productivity growth in market economies:
• Large pace of output and input reallocation
• This is productivity enhancing (market forces)
• But, the magnitude depends somewhat upon sector, country and period
Nick Bloom, Macro Topics, Spring 2009
Defining productivity
Define a simple industry productivity index: Pt
Where:
ωi,t is the productivity of establishment i in period t (i.e. log(labor productivity) or log (TFP))
si,t is the share of establishment i in the industry in period t (i.e. the share of employment or sales in industry employment or sales)
titit sP ,,
Nick Bloom, Macro Topics, Spring 2009
Measuring productivity (ωi,t)
Labor Productivity:
tititi lvaLP ,,,
Three factor TFP:
timtiktiltiti mklyTFP ,,,,3,
Five factor TFP:
tictietimtiktiltiti cemklyTFP ,,,,,,5,
Note: va=log(value added), l=log(labor force), k=log(tangible capital), m=log(materials, e=log(energy), c=log(IT). If IT included need to remove from tangible capital.
Nick Bloom, Macro Topics, Spring 2009
Decomposing productivity (1)
Productivity growth for a balance panel of establishments can be broken down into three terms:
termCross ))((
termBetween )(
termWithin )(
1,,1,,
1,1,,
1,,1,
1,1,,,1
titititi
tititi
tititi
tititititt
ss
ss
s
ssPP
Within term is included in representative agent models, while the between and cross terms would not be
Nick Bloom, Macro Topics, Spring 2009
Decomposing productivity (2)
Allowing for entry and exit requires two more terms:
Exit term )(
Entry term )(
termCross ))((
termBetween )(
termWithin )(
,,
,,
,
,
1,,1,,
1,1,,
1,,1,
1,1,,,1
AverageExitExitti
AverageEntryEntryti
titititi
tititi
tititi
tititititt
titi
titi
s
s
ss
ss
s
ssPP
This is the Bailey, Hulten and Campbell (1992) decomposition
Nick Bloom, Macro Topics, Spring 2009
*
Source: John Haltiwanger
Total reallocation (between, entry and exit) accounts for about ½ of manufacturing TFP growth
*Combines -0.08 “between” and 0.34 “cross”
Nick Bloom, Macro Topics, Spring 2009
(A) Treats all reallocation within establishments as “within” growth• Large establishments in balanced panel (500 employees)
(B) Reallocation terms most likely to be downward biased by miss measured prices (Foster, Haltiwanger and Syversson, 2008)
So in manufacturing re-allocation of factors probably accounts for the majority of productivity growth
This is probably even an underestimate
Nick Bloom, Macro Topics, Spring 2009
Source: Foster, Haltiwanger & Krizan (2000 and 2006)
Reallocation (including entry) accounts for almost all Retail TFP growth
00.10.20.30.40.50.60.70.80.9
1
Manufacturing Retail
ContinuingEstablishments
Net entry
Nick Bloom, Macro Topics, Spring 2009
Massive amounts of micro-heterogeneity – does this effect macrooutcomes:
• Consensus on employment is yes• i.e. Shimer and Hall
• My view on productivity is yes:• Most aggregate TFP growth not “within”, but not much
literature (Cabellero, Engel & Mico, 2006, Bloom, 2007)
• Debate on impact adjustment costs:• Caballero, Engel, Thomas, Veracierto... – another class
Conclusions
Nick Bloom, Macro Topics, Spring 2009
BIBLIOGRAPHYMain sources:Foster, Haltiwanger and Krizan (2000), “Aggregate productivity growth: lessons
from microeconomic evidence”
Also see:Davis and Haltiwanger (1992), “Gross Job Creation, Gross Job Destruction, and
Employment Reallocation”, QJE, 107(3), pp. 819-63. Foster, Haltiwanger and Krizan (2006), “Market selection, reallocation and
restructuring in US retail”, RESTAT