IMF-全球贸易的碎片化：商品核算（英）-2023-WN5.pdf

Fragmentation in Global Trade Accounting for Commodities Marijn A.Bolhuis,Jiaqian Chen,and Benjamin Kett WP/23/73 IMF Working Papers describe research in progress by the author(s)and are published to elicit comments and to encourage debate.The views expressed in IMF Working Papers are those of the author(s)and do not necessarily represent the views of the IMF,its Executive Board,or IMF management.2023 MAR 群内每日免费分享5份+最新资料 群内每日免费分享5份+最新资料 300T网盘资源+4040万份行业报告为您的创业、职场、商业、投资、亲子、网赚、艺术、健身、心理、个人成长 全面赋能！添加微信，备注“入群”立刻免费领取 立刻免费领取 200套知识地图+最新研报收钱文案、增长黑客、产品运营、品牌企划、营销战略、办公软件、会计财务、广告设计、摄影修图、视频剪辑、直播带货、电商运营、投资理财、汽车房产、餐饮烹饪、职场经验、演讲口才、风水命理、心理思维、恋爱情趣、美妆护肤、健身瘦身、格斗搏击、漫画手绘、声乐训练、自媒体打造、效率软件工具、游戏影音扫码先加好友，以备不时之需扫码先加好友，以备不时之需行业报告/思维导图/电子书/资讯情报行业报告/思维导图/电子书/资讯情报致终身学习者社群致终身学习者社群关注公众号获取更多资料关注公众号获取更多资料*The author(s)would like to thank Shekhar Aiyar,Jorge Alvarez,Chikako Baba,Mehdi Benatiya Andaloussi,Wenjie Chen,StephanDanninger,Romain Duval,Christian Ebeke,Luc Eyraud,Pierre-Olivier Gourinchas,Nikolay Gueorguiev,Anna Ilyina,Petya KoevaBrooks,Ting Lan,Chiara Maggi,Papa NDiaye,Martin Stuermer,Petia Topalova,Daria Zakharova,and Robert Zymek.2023 International Monetary Fund WP/23/73IMF Working Paper Strategy,Policy,&Review Department Fragmentation in Global Trade:Accounting for Commodities*Prepared by Marijn A.Bolhuis,Jiaqian Chen,and Benjamin Kett Authorized for distribution by Anna Ilyina March 2023 IMF Working Papers describe research in progress by the author(s)and are published to elicit comments and to encourage debate.The views expressed in IMF Working Papers are those of the author(s)and do not necessarily represent the views of the IMF,its Executive Board,or IMF management.ABSTRACT:We construct a new database which covers production and trade in 136 primary commodities and 24 manufacturing and service sectors for 145 countries.Using this new more granular data,we estimate spillover effects from plausible trade fragmentation scenarios in a new multi-country,multi-sector,general-equilibrium model that accounts for unique demand and supply characteristics of commodities.The results show fragmentation-induced output losses can be sizable,especially for Low-Income-Countries,although the magnitudes vary according to the particular scenarios and modelling assumptions.Our work demonstrates that not accounting for granular commodity production and trade linkages leads to underestimation of the output losses associated with trade fragmentation.RECOMMENDED CITATION:Bolhuis A.Marijn,Jiaqian Chen and Benjamin Kett(2023):Fragmentation in Global Trade:Accounting for Commodities.IMF Working Paper,No.WP 23/73JEL Classification Numbers:F11,F12,F14,F15,F17,F41,F42,F43,Q17,Q27,Q37,Q43 Keywords:Commodities;international trade;sanctions;spillovers;fragmentation Authors E-Mail Address:mbolhuisimf.org,jchenimf.org,bkettimf.org IMF WORKING PAPERS Fragmentation in Global Trade INTERNATIONAL MONETARY FUND 3 WORKING PAPERS Fragmentation in Global Trade Accounting for Commodities Prepared by Marijn A.Bolhuis,Jiaqian Chen,Benjamin Kett IMF WORKING PAPERS Fragmentation in Global Trade INTERNATIONAL MONETARY FUND 4 Contents 1.Introduction.5 2.Data.8 Production and trade data.8 Trade elasticities(short vs.long run).9 Demand elasticities.10 3.Modelling Framework.11 Model.11 Assessing the costs of fragmentation.12 4.Geo-Economic Fragmentation Scenarios.14 5.Results.16 Main Results.16 Robustness checks.20 Trade Elasticities.20 Inter-bloc aggregate imbalances.21 6.Conclusion.24 References.25 Annex I.Data.28 Commodity list.28 Trade Elasticities.29 Annex II.Modelling framework details.30 Full Model.30 Equilibrium using exact hat algebra.34 IMF WORKING PAPERS Fragmentation in Global Trade INTERNATIONAL MONETARY FUND 5 1.Introduction Following several decades of a steady increase in global economic integration,globalization has stalled and may be on the brink of a reversal.The shallow and uneven economic recovery from the Global Financial Crisis(GFC)coincided with a growing number of military conflicts around the world,a deepening skepticism about the benefits of globalization,and a growing populism and protectionism(e.g.,Brexit,trade war between the United States and China).The COVID-19 pandemic has further tested international relations.The war in Ukraine served to split countries along geopolitical lines,further increasing uncertainty over the direction of globalization.Aiyar and others(2023)documents these developments and coins the term“geoeconomic fragmentation”(GEF)to describe a policy-driven reversal of global economic integration often guided by strategic considerations.Motivated by the rising specter of GEF,a growing number of studies have attempted to gauge the potential economic effects of possible fragmentation scenarios(Aiyar and others,2023).This paper aims to quantify the economic costs of fragmentation from an international trade perspective,with a particular focus on production and trade of commodities.More specifically,we examine how various fragmentation scenarios affect output in different country groups by applying a novel multi-country multi-sector model with input-output linkages to a newly developed dataset that accounts for granular production and trade in commodities.To effectively account for spillovers from trade fragmentation,we construct a new dataset that covers a granular level of trade and production in commodities following Fally and Sayre(2019,FS hereafter).FS use detailed data on production and trade from various sources to construct a rich dataset covering trade,production,and prices across a range of commodities.Our dataset extends their work along several dimensions:(i)we update the data to 2019,the most recent pre-pandemic year,from 2016 in FS;(ii)we modify the list of commodities in order to reflect the most“upstream”products,which is important to ensure the characteristics of commodities(such as geographical concentration)are appropriately captured;and(iii)we reconcile our dataset with an otherwise standard input-output(IO)matrix such that the individual commodities sum up to an aggregate sector in the Eora26 database(Lenzen et al.,2012,2013).Overall,our database contains 136 primary commodities along with 24 manufacturing and service sectors for 145 countries.Exploiting the detail of this dataset requires an adapted model which incorporates commodities.While our model has similar building blocks,we depart from FS in several ways.Most importantly,we consider sectoral input-output linkages that allow for feedback loops in production.Intermediate inputs are shown to be important conduits for transmitting shocks across countries(e.g.,Auer et al.,2019;Boehm et al.,2019)and imply substantially larger losses from increasing trade barriers(e.g.,Caliendo and Parro,2015).Moreover,to reduce the data burden we follow Cunat and Zymek(2022),making use of proportionality assumptions in the use of intermediate inputs.We start from an otherwise standard quantitative multi-country multi-sector trade model and distinguish between two types of goods,commodities and non-commodities.The production of non-commodities uses labor,commodities,and non-commodity intermediate inputs,while the production of commodities relies on labor and non-commodity intermediate inputs.Non-commodities are also consumed as final goods.We generate a low price elasticity of demand for commodities by introducing a low elasticity of substitution between commodities and other inputs in the production of non-commodities.IMF WORKING PAPERS Fragmentation in Global Trade INTERNATIONAL MONETARY FUND 6 We then use the model to approximate the impact of trade fragmentation on domestic prices and output.We first show that,up to a first-order approximation,fragmentation has a larger impact on prices in countries and sectors that lose access to a larger share of their pre-fragmentation supply.This impact is particularly large in sectors where the elasticity of substitution between foreign and domestic products is lower.This trade elasticity is a crucial parameter measuring the response of trade to changes in trade costs which we discuss in more detail in the rest of the paper.We also show that the overall effect of fragmentation on a countrys real GDP can be decomposed into the contributions of(i)the direct effect of import prices on final goods,(ii)amplification through input-output linkages,and(iii)the effect on prices of commodities.We calibrate the key model parameters based on the latest existing literature.Our demand elasticities for commodity sectors are sourced from FS,which conducts a meta-analysis of the literature.The trade elasticities are calibrated based on recent work by Fontagn et al.(2022)and provide conservative results while being well in line with other estimates in the literature(see Data section).Notably,the two principal commodity subsectors have the lowest trade elasticities across all sectors,at 3.4 for Mining and Quarrying,and 2.9 for Agriculture(compared to an average across sectors of 6).Building on the most recent work on estimating trade elasticities,we also consider short-run trade elasticities which,due to adjustments costs,are shown by Boehm et al.(forthcoming)to be significantly lower than long-run elasticities.Similar to FS,we find that properly accounting for trade and production in commodities(i.e.,using sectoral data disaggregated into product level commodities)substantially increases the adverse economic impact of trade fragmentation compared with models which implicitly assume perfect substitutes among commodities.Comparing the baseline equilibrium(2019 global trade barriers)to global autarky,we find that the output losses more than double for Low-Income Countries(LICs),who are heavily dependent on trade in commodities,while for Advanced Economies(AEs)and Emerging Market economies(EMs)the welfare losses increase by 4 and 25 percent respectively.Intuitively,trade barriers are much more costly for products which can only be sourced from a relatively small number of countries and for which demand is relatively inelastic.The model is used to explore several hypothetical scenarios that illustrate the cost of a more fragmentated global trade network.We make a distinction between two scenarios.In the mild fragmentation scenario(Strategic Decoupling)there is no trade between the US-EU and Russia,and no trade in high-tech sectors between the US-EU and China,but the rest of the world(RoW)are free to trade with both groups.In the severe fragmentation scenario(Geo-economic Fragmentation),there is no trade between EU-US and Russia-China and the RoW joins one of the two groups depending on the strength of the trade link with either the US or China,resulting in zero trade with the other group.Global output losses are estimated to fall by between 0.3 percent and 2.3 percent in the long run depending on the fragmentation scenario.Moreover,the impacts are heterogenous across income groups.Specifically,in the mild fragmentation scenario,LICs benefit from trade diversion as the trade barriers they face remain unchanged relative to the baseline;however,in the more severe fragmentation scenario,their output drops by 4.3 percent over the long run.These results underscore the vulnerability of LICs to trade barriers and the risks of forcing them to choose groups.It is,nonetheless,important to note that there is a wide range of potential estimates of the size of fragmentation-induced losses,depending on the modeling assumptions.For example,calibrating the model with different estimated trade elasticities in the literature,we find the global GDP loss ranges between 1.9 and 7.0 percent in the more severe fragmentation scenario.Moreover,these simulations do not reflect the full effects of global economic fragmentation,as some of the important channels which would imply larger economic losses are not captured.Another set of scenarios reveals the sensitivity of countries to IMF WORKING PAPERS Fragmentation in Global Trade INTERNATIONAL MONETARY FUND 7 trade restrictions in different product groups.In particular,we find that AEs and EMEs are most vulnerable to disruption in trade in energy and high-tech manufacturing sectors,whereas LICs see the largest output loss following barriers to trade in agricultural goods.The fast-growing literature on the costs of sanctions and global fragmentation has generated a wide array of quantitative estimates,reflecting the consideration of different channels as well as different assumed fragmentation scenarios.IMF(2022)investigates the effect of eliminating trade in the aggregated high-tech and energy sectors across rival blocs which are determined based on the vote to condemn Russias invasion of Ukraine at the United Nations General Assembly(UNGA)in March 2022.The results suggest a loss of about 1.2 percent of world GDP,which increases to 1.5 percent when barriers to trade are extended to other sectors as well.Cerdeiro et al.(2021)employ a set of structural models to examine the costs of three different layers of fragmentation(trade,sectoral misallocation,and foreign knowledge diffusion),across a range of fragmentation scenarios.Their estimated welfare costs range from zero(as some countries gain from trade diversion)to 8.5 percent when accounting for all three layers of fragmentation.Bekkers and Goes(2022)focus on knowledge diffusion across countries,with the global economy divided into an Eastern bloc and a Western bloc based on UNGA voting records.The results show a range of losses from 0.4 percent of GDP for some countries in a mild fragmentation scenario to 12 percent for the most affected countries under full technological decoupling.Javorcik et al.(2022)examine fragmentation through the lens of friend-shoring,finding output losses of between 0.1 percent and 4.6 percent of GDP depending on the country and scenario.Our paper differs from existing papers in that we focus on the international trade channel specifically,and we account for granular trade and production of commodities,whereas previous studies assume commodities such as copper and diamond are perfect substitutes.This underestimates the cost of fragmentation for the global economy,with a particular impact on countries that are more exposed to commodity trade.Moreover,we calibrate our model with the estimated trade elasticities from the latest available literature and capture both short and long run costs of trade fragmentation.Our paper also contributes to the literature on the effects of sanctions related to energy commodities for European countries.Bachmann et al.(2022)find a Russian gas shut-off(i.e.,a 30 percent gas supply shock)would affect German Gross National Expenditure by-0.7 to-2.3 percent,depending on the elasticity of substitution used.Applying a similar framework but incorporating uncertainty and second-round effects,Lan et al.(2022)estimate that Germanys real GDP will fall by 1.4 percent in 2022 and 2.7 percent in 2023 under the assumption that households adjust consumpt