开放经济中的非正规性与冲击传播

Informality and ShockPropagation in an OpenEconomy Sandra Lizarazo and Brandon Joel Tan WP/25/190 IMF Working Papersdescribe research inprogress by the author(s) and are published toelicit comments and to encourage debate.The views expressed in IMF Working Papers arethose of the author(s) and do not necessarilyrepresent the views of the IMF, its Executive Board,or IMF management. 2025SEP IMF Working Paper Western Hemisphere Department Informality and Shock Propagation in an Open EconomyPrepared bySandra Lizarazoand Brandon Joel Tan Authorized for distribution byNigel ChalkSeptember 2025 IMF Working Papersdescribe research in progress by the author(s) and are published to elicitcomments and to encourage debate.The views expressed in IMF Working Papers are those of theauthor(s) and do not necessarily represent the views of the IMF, its Executive Board, or IMF management. ABSTRACT:The informal sector accounts for a large fraction of the economy and labor force in manyemerging market and developing economies. This paper develops a dynamic stochastic general equilibriummodel of a small open economy with an informal sector. Nominal price and wage rigidities are present in theformal sector, while prices and wages are flexible in the informal sector. Production of traded goods rely moreon formal inputs (which can be produced at home or imported) while non-traded goods rely more on informalinputs. We show that, despite its costs, the informal sector can provide a flexible margin of adjustment in laborand product markets which helps buffer the impact of domestic and external shocks. 1Introduction The informal sector accounts for a large fraction of the economy and labor force in manyemerging market and developing economies.1 According to the International Labour Orga-nization, in several Sub-Saharan African economies such as Niger, Burundi, Chad, and theDemocratic Republic of the Congo, informality rates exceed 90%. This pattern is also preva-lent across parts of South Asia (e.g., India and Bangladesh) and Latin America (e.g., Boliviaand Guatemala), where rates remain well above 80%. In contrast, high-income economies,particularly in Europe, report informality rates below 5%, with countries like Switzerland,Austria, and Belgium seeing less than 1.5% of their labor force in informal employment. While informality is associated with several structural weaknesses – such as lower pro-ductivity, lower growth in equilibrium, a weaker tax base, job and income insecurity, andlimited access to social protection (International Monetary Fund, 2021), the informal sectorcan provide a flexible margin of adjustment in labor and product markets when countries arefaced with economic shocks. Informal employment tends to be countercyclical (Fern´andezand Meza, 2015), expanding during downturns as formal employment contracts and firms re-duce their workforce. Additionally, the informal sector demonstrates greater wage and priceflexibility in both its labor and product markets (Agudelo and Sala, 2017; Ahmed et al., 2014), enabling faster adjustments to changing economic conditions. In this paper, we develop a dynamic stochastic general equilibrium model of a small openeconomy with an informal sector to analyze the role informality plays in the propagation ofdomestic and foreign shocks. In our model, nominal price and wage rigidities are present inthe formal sector, while prices and wages are flexible in the informal sector. Price stickinessin the goods market comes from Calvo price adjustment for intermediate goods. Similarly,wage stickiness in the formal sector arises from an ex-ante wage bargaining arrangementconducted by unions. Production of traded goods relies more on formal intermediate goods(which can be produced at home or imported) while non-traded goods relies more on informalintermediate goods.The informal sector has lower productivity and is characterized bytax evasion; thus, a larger informal sector results in reduced tax revenue, decreased publicinvestment, and lower overall output. The model reveals that the informal sector can help buffer the impact of domestic andexternal shocks.Since formal input prices and wages are sticky and do not immediatelyadjust downwards in response to a negative shock, production shifts to informal inputs,consumption shifts to non-traded goods, and labor shifts to the informal sector. This resultsin a smaller impact on output, employment and exports, and lower inflation with informalitythan without. We calibrate the model to the Bolivian economy, where the informal sector is large at 85%of employment and 68% of GDP, and simulate the effects of a range of macroeconomic shocks.We compare the responses of the full model—including an informal sector—with those ofa counterfactual specification without informality.The results suggest that informality inBolivia plays a significant shock-absorbing role: it dampens the adverse effects of negativesupply-side shocks—such as productivity de