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VOL. 12, NO. 14 • DECEMBER 2017

DALLASFED

Economic
Letter
Demand Shocks Fuel
Commodity Price Booms and Busts
by Martin Stuermer

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ABSTRACT: Demand shocks
due to rapid industrialization
have driven commodity price
booms throughout history. As
periods of industrialization lose
steam and supply catches
up, busts follow after about
10 years. A new dataset of
price and production levels
of 12 commodities provides
evidence of this behavior from
1870 to 2013.

B

ooms and busts in commodity markets are a particularly
important part of the global
economy. They affect inflation and consumer spending, determine
investment and welfare in producing
nations. They also influence growthenhancing institutions and may even
lead to civil unrest.
Understanding which shocks drive
these low-frequency price movements
and how long they persist is important in
formulating environmental and resource
policies, for the conduct of macroeconomic policy, and, most importantly, for
investment decisions involving extractive
and agricultural sectors of the economy.
Commodity prices are driven by
shocks on the supply and demand sides.
For example, a commodity supply shock
is an unexpected decline in crop yield
due to adverse weather, which shifts
the supply curve inward and increases
prices.
An aggregate commodity demand
shock changes the demand for all commodities at the same time. For example,
China’s rapid industrialization led to
stronger-than-expected increases in the
demand for a broad variety of commodities such as copper, oil and wheat over
the past decade.1
Thus, examining the effects of shocks
on commodity prices is an intriguing

avenue of research.2 While the literature
on modeling oil markets has examined
only a handful of boom-and-bust phases
since the early 1970s, this analysis of
commodity markets is based on a new
dataset of price and output levels for 12
agricultural, metal and soft commodities
for the period 1870 to 2013.
China’s effect on commodity markets
is not a new phenomenon. Throughout
history, demand shocks due to rapid
industrialization have driven commodity
price booms.
Aggregate demand shocks strongly
predominate over supply shocks as drivers of price booms across a broad variety
of commodities. Demand shocks strongly
affect prices for about 10 years, while
commodity supply shocks impact prices
for roughly five years. As periods of
industrialization lose steam and supply
catches up, busts follow. Prices return to
their stable or declining trends.

Commodities Dataset Created
A dataset encompassing global
output and prices for 12 commodities—
barley, corn, rice, rye, coffee, cotton,
cottonseed, sugar, copper, lead, tin and
zinc—was assembled covering the 143year study period (Chart 1).
The commodity markets selected
exhibit characteristics that make a longrun analysis feasible. Specifically, there

Economic Letter
Chart

1

Booms, Busts Not a New Phenomenon

Annual real price indexes for 12 commodities, 1900 = 100
300

Metals

Copper

Lead

Tin

Zinc

200

100

0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005

300

Grains

Barley

Corn

Rice

Rye

200

each commodity price. The “aggregate
demand shock” (for example, unexpected increased in commodity demand due
to rapid industrialization) is based on the
assumption that this shock can trigger
investment and innovation, and subsequent long-run effects on overall output.3
By comparison, it is assumed that
a “commodity supply shock”—such as
cartel action or the weather—only affects
global gross domestic product (GDP) for
a couple of years. This is consistent with
evidence that oil supply shocks have had
short-lived effects on U.S. GDP.4
Any residual shock—or one that isn’t
attributable to an aggregate shock or a
commodity supply shock—is a “commodity market-specific demand shock.”
This type of shock is assumed to only
affect capacity utilization and poses no
long-run effects on global GDP or commodity production.

Booms, Busts Explained
100

0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
400

Soft Commodities

Coffee

Cotton

Cottonseed

Sugar

300

200

100

0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
SOURCE: “What Drives Commodity Booms and Busts?” by David Jacks and Martin Stuermer, Federal Reserve Bank of
Dallas Working Paper no. 1614, November 2016.

is longstanding evidence of an integrated
world market; there is no strong indication of sudden change in how the commodity is used, and there is a high degree
of product homogeneity. Thus, the 12
commodities selected have long-term
characteristics that mineral commodities
such as iron ore or crude oil only gained
relatively recently.

Identifying Price Shocks
Shocks are unexpected shifts in the

2

supply or demand curves of a commodity market. An underlying idea is that
firms do not anticipate these shocks.
Because it’s not easy for supply or
demand to fully respond, there are either
supply shortfalls or oversupply, leading
to price increases or decreases as firms
discover they are either underinvested or
overinvested.
The econometric model employed
here allows identification of the contribution of three types of shocks to

Econometric modeling allows assessment of the contribution of each type of
shock to commodity prices over time.
Chart 2 represents a counterfactual
simulation of what the prices of specific
commodities would have been solely in
the presence of aggregate commodity
demand shocks.
The collective story that emerges
suggests that although the proportional
contribution of the aggregate commodity
demand shocks naturally varies across
the different commodities, the accumulated effects broadly follow the same pattern. Thus, while aggregate commodity
demand shocks affect prices to different
degrees, they affect the real commodity
prices at the same time. These results
then suggest that aggregate commodity
demand shocks have a common source.
This interpretation of aggregate commodity demand shocks is in line with
what economic history suggests about
global output fluctuations. Historical
decompositions start in 1875, when prices were depressed due to the negative
accumulated effects of aggregate commodity demand shocks on prices during
the first—but somewhat forgotten—Great
Depression.
The effects of subsequent aggregate
commodity demand shocks are in line
with historical occurrences of business

Economic Letter • Federal Reserve Bank of Dallas • December 2017

Economic Letter
cycles in major economies. For example,
the effects of the large negative aggregate
commodity demand shock in 1907 can
be associated to the so-called Panic of
1907. Likewise, in the early 1930s, real
prices plummeted as the (second) Great
Depression reduced global demand for
commodities.
After World War II, positive aggregate commodity demand shocks led to
increases in real commodity prices as
re-industrialization and re-urbanization
in much of Europe and Japan proceeded,
followed by economic transformation of
the East Asian Tigers (following Japan’s
lead).
Negative aggregate commodity
demand shocks are evident in the late
1970s, the early 1980s and the late 1990s,
respectively corresponding to the global
recessions of 1974 and 1981 and the
Asian financial crisis of 1997. These are
followed by a series of positive aggregate
commodity demand shocks emerging
from the late 1990s and early 2000s due
to unexpectedly strong global growth,
driven by the industrialization and
urbanization of China.
Finally, the lingering effects of the
global financial crisis are also clearly
visible.

ther to 16 percent in the period after
World War II.
At the same time, the average share
of aggregate commodity demand shocks
has increased from 29 percent in the preWorld War I period to 34 percent during
the interwar period and up to 38 percent
in the post-World War II period.
On average, the effects of aggregate
commodity demand shocks are the most

Chart

2

persistent, with effects lingering up to
10 years. Commodity market-specific
demand shocks are slightly less persistent but with effects also lasting up to 10
years in some cases. Finally, effects of
commodity supply shocks, for the most
part, are insignificant. The sugar and tin
markets are exceptions to this generality,
with significant effects lasting up to five
years.

Commodity Prices React to Demand Shocks Simultaneously

Annual real price indexes for 12 commodities, 1900 = 100
1.0

Grains

Rye

Barley

Corn

Rice

0.5

0

–0.5

–1.0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
1.0

Soft Commodities

Coffee

Cottonseed

Sugar

Cotton

0.5

Demand Dominates Supply
From 1871 to 2013, aggregate commodity demand shocks explained 32–38
percent of the variation in real commodity prices (across the three types of commodities examined here), while commodity market-specific demand shocks
explained 42–50 percent (Table 1A).
These two types of shocks, thus, caused
an appreciable portion—74–88 percent—
of medium- and long-run fluctuations in
real commodity prices.
Conversely, commodity supply
shocks played a rather secondary and
transient role, explaining only 18–20 percent of the variation. This result is fairly
consistent across agricultural, mineral
and soft commodities.
Averages for three subperiods based
on the full sample (Table 1B–D) show
that commodity supply shocks have lost
importance over time, as their average
share declined from 24 percent in the
period before World War I to 23 percent
during the interwar period and fell fur-

0

–0.5

–1.0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
1.0
0.8

Metals

Lead

Copper

Tin

Zinc

0.6
0.4
0.2
0
–0.2
–0.4
–0.6
–0.8
–1.0
1875 1885 1895 1905 1915 1925 1935 1945 1955 1965 1975 1985 1995 2005
NOTE: Charts show a counterfactual simulation of what the prices of specific commodities would have been solely in the
presence of aggregate commodity demand shocks.
SOURCE: “What Drives Commodity Booms and Busts?” by David Jacks and Martin Stuermer, Federal Reserve Bank of
Dallas Working Paper no. 1614, November 2016.

Economic Letter • Federal Reserve Bank of Dallas • December 2017

3

Economic Letter

Table

1

Different Types of Shocks Explain Commodity Price Booms, Busts

Percentage share of each type of shock that explains commodity price fluctuations
A: 1871–2013
Aggregate commodity
demand shock

Commodity
supply shock

Commodity
market-specific demand shock

Grains

32

18

50

Metals

38

20

42

Softs

34

20

44

Total

35

20

46

Aggregate commodity
demand shock

Commodity
supply shock

Commodity
market-specific demand shock

Grains

26

23

52

Metals

33

24

44

Softs

27

24

48

Total

29

24

47

Aggregate commodity
demand shock

Commodity
supply shock

Commodity
market-specific demand shock

Grains

32

19

49

Metals

34

27

38

Softs

35

19

46

Total

34

23

45

Aggregate commodity
demand shock

Commodity
supply shock

Commodity
market-specific demand shock

Grains

37

16

47

Metals

42

16

42

Softs

38

18

45

Total

38

16

46

B: 1871–1913

C: 1919–39

D: 1949–2013

SOURCE: “What Drives Commodity Booms and Busts?” by David Jacks and Martin Stuermer, Federal Reserve Bank of Dallas
Working Paper no. 1614, November 2016.

Persistent, Low Prices
After examining the drivers of real
commodity prices in the long run among
different types of commodities, aggregate

DALLASFED

commodity demand shocks and commodity market-specific demand shocks
appear to strongly dominate over commodity supply shocks in driving fluctua-

Economic Letter

is published by the Federal Reserve Bank of Dallas.
The views expressed are those of the authors and
should not be attributed to the Federal Reserve Bank
of Dallas or the Federal Reserve System.
Articles may be reprinted on the condition that
the source is credited to the Federal Reserve Bank
of Dallas.
Economic Letter is available on the Dallas Fed
website, www.dallasfed.org.

tions of real commodity prices over a
long period of time.
The results suggest that the price
effects of the large commodity demand
shocks attributable to China in 2003–07
and 2009–11 will dissipate. In the
absence of additional positive commodity demand shocks, it appears that current
prices may stay low while abundant supplies are consumed. Commodity exporters should, thus, prepare for a prolonged
period of depressed commodity prices.
Stuermer is a research economist in the
Research Department at the Federal Reserve Bank of Dallas.

Notes
See “Industrialization and the Demand for Mineral
Commodities” by Martin Stuermer, Journal of International Money and Finance, vol. 76, 2017, pp. 16-27,
for an empirical exploration of the relationship between
industrialization and mineral commodities.
2
For details on the data, methodology and results, see
“150 Years of Boom and Bust: What Drives Mineral
Commodity Prices?” by Martin Stuermer, Macroeconomic Dynamics, 2018, forthcoming, and “What Drives Commodity Booms and Busts?” by David Jacks and Martin
Stuermer, Federal Reserve Bank of Dallas Working Paper
no. 1614, December 2016.
3
For each commodity market, a Structural Vector
Autoregressive Model with long-run restrictions is used.
It includes three endogenous variables—global gross
domestic product (%), global commodity production (%)
and world commodity price (ln). The model also controls
for constant, linear trends and the world war periods.
4
See “Not All Oil Price Shocks Are Alike: Disentangling
Demand and Supply Shocks in the Crude Oil Market,” by
Lutz Kilian, American Economic Review, vol. 99, no. 3,
June 2009, pp. 1053–69.
1

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