Financialization and the rise in co-movement of commodity prices

Between January 2000 and June 2008, the FAO food price index rose by 96%. Besides the magnitude, the price rise was remarkable for the broad range of commodities affected; prices of agriculture commodities, energy, and metals all rose and fell together. These dramatic developments coincided with a massive inflow of investment in the commodities futures market, and the rise of commodities as an investment class. In this paper, I study causal links between the increase in the co-movement between commodity prices and financialization of the commodities futures market. I extract common factors from a group of 40 commodities using the PANIC method and include it in a factor-augment VEC model along with a proxy of financialization. Results show that financialization of the commodities futures markets can explain the recent rise in co-movement between commodity prices, after accounting for macroeconomic variables.     

Commodity Prices and the Terms of Trade

On combining national terms-of-trade data for developing countries with world prices of internationally traded primary commodities, it is found that variation in the world prices of three or fewer key exported commodities account for 50% or more of the annual variation in the terms of trade of a typical developing country. A considerable fraction of the variation is specific to a particular commodity and, given that the overall importance of primary commodities differs across developing countries, it is possible to account for much of the heterogeneity across them. It is concluded that commodity price fluctuations should be central features of two related literatures: studies of business cycle transmission across developing and industrialized nations, and empirical work aimed at constructing perpetual claims on developing country incomes as suggested by Shiller in 1995.     

国际大宗商品价格至中国上下游价格的时变传导效应*

本文采用国际大宗商品价格、中国国内总产出、货币政策变量和上下游价格数据，通过构建多个TVPVARSV模型考察了1997—2017年国际大宗商品价格向中国上下游价格的时变传导效应。研究表明，由于受到来自国际生产资料和生活资料分类价格变动趋势异质性、上下游价格传导路径异质性和价格信息传导机制结构性变动的影响，国际大宗商品价格向中国上下游价格的传导效应呈现时变特征。国际大宗商品价格对国内上游价格传导稳定，但对下游价格传导长期下降，这解释了我国PPI和CPI走势的偏离现象。     

Global commodity cycles and linkages: a FAVAR approach

In this article, we examine linkages across non-energy commodity price developments by means of a factor-augmented VAR model (FAVAR). From a set of non-energy commodity price series, we extract two factors, which we identify as common trends in metals and food prices. These factors are included in a FAVAR model together with selected macroeconomic variables, which have been associated with developments in commodity prices. Impulse response functions confirm that exchange rates and economic activity affect individual non-energy commodity prices, but we fail to find strong spillovers from oil to non-oil commodity prices or an impact of the interest rate. In addition, we find that individual commodity prices are affected by common trends captured by the food and metals factors.     

Market volatility and the dynamic hedging of multi-commodity price risk

Commodity cash and futures prices experienced a severe boom-and-bust cycle between 2006 and 2009. Increases in commodity price volatility have raised concerns about the usefulness of commodity futures and options as risk management tools. Dynamic hedging strategies have the potential to improve risk management when conditional (co)variances depart significantly from their unconditional, long-run counterparts and may be useful to decision-makers despite their greater complexity and higher transaction costs. We propose a Nonparametric Copula-based Generalized Autoregressive Conditional Heteroscedastic (NPC-GARCH) approach to estimate time-varying hedge ratios, and evaluate the benefits of dynamic hedging during four sub-periods between 2000 and 2011 using a stylized Texas cattle feedlot management problem. The NPC-GARCH approach allows for a flexible, nonlinear and asymmetric dependence structure between cash and futures prices for different commodities. We find that NPC-GARCH dynamic hedging performs better than either static, GARCH-Dynamic Conditional Correlation (DCC) or GARCH-Baba, Engle, Kraft and Kroner (BEKK) hedging in terms of lower tail risk (expected shortfall), but that there is no significant difference between hedging approaches in terms of portfolio variance reduction.     

Jumps and volatility dynamics in agricultural commodity spot prices

The spot commodities market exhibits both extreme volatility and price spikes, which lead to heavy-tailed distributions of price change and autocorrelation. This article uses various Lévy jump models to capture these features in a panel of agricultural commodities observed between January 1990 and February 2014. The results show that Levy jump models outperform the continuous Gaussian model. Our results prove that assuming a constant volatility or even a deterministic volatility and drift structure of agricultural commodity spot prices is not realistic and is less efficient than the stochastic assumption. The findings demonstrate an interesting correlation between volatility and jumps for a given commodity i, but no relationship between the volatility of commodity i and the probability of jumps of commodity j.     

The transmission of world commodity prices to domestic markets under policy reforms in developing countries

This paper examines the degree to which world price signals have been transmitted into domestic prices for eight countries and ten commodities, a total of 31 country/commodity pairs. The main characteristic of these countries was that they all undertook substantial policy reforms during the mid‐1980s to early 1990s. The paper investigates the effect of reforms on the speed at which signals were transmitted to domestic markets and on the extent of price transmission. We find that Chile, Mexico, and Argentina are the only countries whose domestic commodity markets were integrated with world markets. For the remaining cases (Ghana, Madagascar, Indonesia, Egypt, and Colombia) in only a few country/commodity pairs is there some passthrough of world price changes. In terms of the effects of policy reforms, in the majority of the cases the hypothesis of a structural break following the reform year is rejected.     

Long-run waves or short-run fluctuations – what establishes the correlation between oil and food prices?

The strong correlation between food prices and energy prices has gained much attention in the public debate. In this article, we focus on the so-called excess co-movement, which is the correlation between crude oil price and the prices of food commodities after controlling for economic activity. We use a frequency domain Granger causality test to analyse short-run and long-run relationships between crude oil prices and prices of food commodities. For important biofuel inputs like maize, soybeans, rapeseed and EU sugar, we find evidence for long-run Granger causality in particular for the period after 2007. This supports the hypothesis that the increasing biofuel production creates the link between the prices of crude oil and food commodities. However, we also find short-run Granger causality for various food commodities. This result is more in line with herd behaviour or speculation in commodity markets.     

A key determinant of commodity price Co-movement: The role of daily market liquidity

Daily price co-movement across different commodity classes and its key determinant are investigated in this paper. Using co-integration and Granger causality analysis, we identify a common liquidity factor which drives prices of five commodities (oil, silver, gold, corn, live cattle) to move along a common trend. When the market becomes more (less) liquid, all commodity prices tend to move up (down) in the same direction. As a result, such liquidity-driven price co-movement across different commodity classes is likely to generate aggregate price shocks and amplify inflation volatility. As a practical implication of our findings, policy makers ought to be able to draw valuable lessons from monitoring daily commodity liquidity dynamics as a timely bellwether for incipient inflation and to more effectively control inflation risk.     

Cointegration relationships and hedonic pricing of differentiated commodities: an application to price dynamics in the US dairy sector

This study investigates the implications of hedonic pricing for price dynamics of differentiated commodities. A conceptual model of hedonic pricing is developed under a Leontief technology, showing how commodity prices reflect the underlying value of their components. Implications for the existence of cointegration relationships among commodity prices are derived. An application to the pricing and dynamics of selected US dairy commodities is presented. It provides evidence on the role of component valuation in the dynamics of dairy commodity prices in the short run as well as in the long run. Distinguishing between market regime and government regime (when the government price support is active), the analysis finds significant differences in dairy price dynamics between the two regimes.     

Erratic monetary policy and the dispersion of commodity prices

This paper develops a closed economy macroeconomic model with many goods, where information flows are not instantaneous. Economic agents form rational expectations of future economic variables based on present information, and measure the future price level with a true cost-of-living index that allows for substitutions among commodities as relative prices change. The major inference drawn from our model is that, when information flows are imperfect, an increase in the variance of the money supply injects noise into economic agents forecasts of prices, and increases the equilibrium level of dispersion in commodity prices.     

How index investment impacts commodities: A story about the financialization of agricultural commodities

This paper focuses on the impact of financial investors on agricultural prices, a phenomenon known as the financialization. In this aim, we check whether financial mechanisms drive extreme values and the mean of agricultural returns in the same way. Relying on the Threshold AutoRegressive Quantile (TQAR) methodology, we find evidence of reinforcement linkages between equity and agricultural markets since 2004, corresponding to the rise in inflows of institutional investors in commodity markets. These results show that agents impact more deeply commodity markets when the commodity index value is high. In addition, in extreme quantiles (0.75 and 0.90) of agricultural returns, the relationship between agricultural and stock returns is always significant when the commodity index return is in the higher regime. This finding suggests that, stock markets had a greater impact on agricultural price dynamics during the extreme movements which occurred during the 2007–2008 financial crisis, highlighting a potential influence of financial markets on the financialization of commodities.     

Cyclicality of commodity markets with respect to the U.S. economic policy uncertainty based on granger causality in quantiles

Given the importance of the U.S. in global commodity markets, the goal is to explore whether U.S. economic policy uncertainty impacts the price performance of certain commodities. The analysis uses the Granger causality in quantiles method that allows us to test whether there are different effects under different market conditions. The results document that economic uncertainty impacts the returns on the commodities considered, with the effects clustering around the tail of their conditional distribution. Robust evidence was obtained under alternative definitions of uncertainty.     

实际汇率变动对商品国内价格的影响研究

本文从理论与实证两方面对实际汇率以及汇率波动性的变动对中国出口商品国内价格的影响进行了研究。理论分析强调了汇率对出口商品国内价格的影响方向取决于商品的需求价格弹性。对我国1990—2002年共12种商品平行数据的实证分析说明了汇率波动性增加可能导致部分初级产品国内价格水平的下降。全文分析强调了实际汇率波动性对国内商品价格的影响。     

Asset arbitrage and the price of oil

It is commonly understood that macroeconomic shocks influence commodity prices and that one channel for this is the link between interest rates, expected future asset returns and stock-holding. In this paper the link is extended to the petroleum market with the recognition that recorded stocks of oil comprise a small share of annual demand and that the parallel with storable commodities is the decision to produce the oil in the first place, as opposed to holding it in the ground as reserve. Oil reserves are then a key asset in producing countries, which is arbitraged against financial assets. Thus, when the yield on financial assets falls, retaining oil reserves becomes more attractive to producing countries, which then have less incentive to accommodate demand rises, and so the oil price rises. This perspective on oil pricing is modeled in a dynamic multi-region general equilibrium framework in which regional households manage portfolios of assets that include oil reserves. When the model is calibrated to match observed data over two decades, simulation results indicate that asset arbitrage made a large contribution to the high pre-GFC oil price.     

Interdependencies in the energy–bioenergy–food price systems: A cointegration analysis

The present paper studies the interdependencies between the energy, bioenergy and food prices. We develop a vertically integrated multi-input, multi-output market model with two channels of price transmission: a direct biofuel channel and an indirect input channel. We test the theoretical hypothesis by applying time-series analytical mechanisms to nine major traded agricultural commodity prices, including corn, wheat, rice, sugar, soybeans, cotton, banana, sorghum and tea, along with one weighted average world crude oil price. The data consists of 783 weekly observations extending from January 1994 to December 2008. The empirical findings confirm the theoretical hypothesis that the prices for crude oil and agricultural commodities are interdependent including also commodities not directly used in bioenergy production: an increase in oil price by 1 $/barrel increases the agricultural commodity prices between 0.10 $/tonne and 1.80 $/tonne. Contrary to the theoretical predictions, the indirect input channel of price transmission is found to be small and statistically insignificant.     

COMMODITY BALANCES AND NATIONAL ACCOUNTS: A SAM PERSPECTIVE

This paper is concerned with the treatment of commodity and activity balances in a national accounts context. It makes use of a general method for reducing the size of a social accounting matrix (SAM) by apportioning the elements of one or more accounts to the rest. The national accounts are looked at in terms of their usefulness for policy analysis, not least analysis of the impact of price changes. The SNA convention of separately distinguishing activities and commodities is endorsed. However, in contrast to the SNA, it is argued that for analytic purposes commodity transactions should be recorded at market prices, with a separate account for each of the markets for a given commodity in which a distinct price prevails. The SNA SAM is shown to be a reduced form of the SAM resulting from this recommended treatment of commodity transactions, while a further round of reductions (apportionments) yields SAMs which are familiar from input-output analysis, in which activities and commodities are not separately distinguished. It is argued that no special effort would be required to produce SAMs in which commodity balances are recorded at market prices as recommended here (the necessary data are also required to produce the conventional SNA tableaux), and that all reduced form versions of such SAMs, including the SNA, are inferior as a basis for the analysis of price effects on the structure of production.     

Futures basis,inventory and commodity price volatility: An empirical analysis

We employ a large dataset of physical inventory data on 21 different commodities for the period 1993–2011 to empirically analyze the behavior of commodity prices and their volatility as predicted by the theory of storage. We examine two main issues. First, we analyze the relationship between inventory and the shape of the forward curve. Low (high) inventory is associated with forward curves in backwardation (contango), as the theory of storage predicts. Second, we show that price volatility is a decreasing function of inventory for the majority of commodities in our sample. This effect is more pronounced in backwardated markets. Our findings are robust with respect to alternative inventory measures and over the recent commodity price boom.     

Consumption patterns in Sri Lanka: a decomposition analysis

Knowing consumer reaction to changes in prices and income is important in formulating microeconomic policies, such as public utility prices and commodity taxation. This paper analyses the consumption patterns of consumer goods grouped into eight broad commodities in Sri Lanka during the period 1975–2016, using a system-wide framework. The analysis indicates that Sri Lankan consumers allocate more than half of their income to food and nearly four fifths of their income to food, housing, and transport combined. The estimated income and own-price elasticities reveal that food, housing, medical care, and transport are necessities; clothing, durables and recreation are luxuries; and demand for all commodities is price inelastic except for recreation. To investigate the consumption growth pattern, we decomposed the growth in consumption and change in budget shares of the eight commodities into income, relative price, and change in taste. We also simulated per capita consumption expenditure of the eight commodities under various policy scenarios and found that income growth has played a significant role in Sri Lankan consumption patterns.     

A model of commodity prices after Sir Arthur Lewis

We develop an idea from Arthur Lewis' paper on unlimited supplies of labor to model the long-run behavior of the prices of primary commodity produced by poor countries. Commodity supply is assumed infinitely elastic in the long run, and the rate of growth of supply responds to the excess of the current price over the long-run supply price. Demand is linked to the level of world income and to the price of the commodity, so that price is stationary around its supply price, and commodity supply and world income are cointegrated. The model is fitted to long-run historical data.