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HAL Id: hal-00721633

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Responses of African economies to the international

economic shocks: an empirical study.

Giscard Assoumou Ella

To cite this version:

Giscard Assoumou Ella. Responses of African economies to the international economic shocks: an empirical study.. 2012. �hal-00721633v2�

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Responses of African economies to the

international economic shocks: an

empirical study.

Giscard ASSOUMOU-ELLA*, LEAD (Laboratoire d’Economie Appliquée au Développement), Université du Sud Toulon-Var.

Abstract

The objective of this paper is first to verify the assumption of decoupling or no decoupling African economic conjunctures and international economic shocks. Our study has tested this assumption in 15 African countries using a SVAR model for the period 1970-2007 and the results suggest that there is no decoupling. In fact 12 countries are exposed to OEDC GDP per capita shocks, six to Federal funds effective rate shocks and five to World price of oil shocks. Furthermore, we investigate the viability of an economic and monetary union creation for the African countries and a unified currency using the comparative of the reaction of any African economy to those international shocks. The impulse response functions of the African economies after an international income, monetary or price shocks tend to be in general more or less similar. According to this indicator, we are optimistic for the possibility and the viability of this project.

Keywords:

African economies; international economic shocks; SVAR model

JEL classification:

C32 ; E32 ; F44

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1. Introduction

African countries produce and export essentially raw materials toward advanced and emerging economies (Madeley, 2003). Contrary to the assumption of decoupling for the economic cycles, these countries are exposed to the international economic shocks. Berman and Matin (2009) argue that an international industrial crisis would have a big impact on African economies because the growth and development of these economies depend on the export of raw materials. For example, during the 2009 Global Financial Crisis, the “average economic growth in Africa slowed to 1%, from an annual average of over 6% to 1% during the previous five years, before rebounding to 4% in 2010”, (IMF, 2010). An international economic crisis leads to a contraction in global trade. In African economies this is associated with the collapse of the primary commodity exports and a decrease in foreign direct investment, migrant worker remittances and foreign aid (CRS, 2010). We can also enumerate the import and tourism transmission channels.

Africa is composed of several regional economic communities and monetary zones. The continental politic organization, the African Union, projects to create an economic and monetary union for the African countries and a unified currency, similar to the euro. The comparative of the reaction of any African economy to the international economic, monetary and prices shocks is a good indication to study the viability of this project.

Finally, our paper investigates the assumption of decoupling or no decoupling African economic conjunctures and international economic shocks. If the assumption of no decoupling is valid, we analyze the impulse response functions of any African country to the three types of crises that have affected advanced economies in recent years: international monetary shocks, international price shocks and international income shocks. Following these international shocks, are the responses of African economies similar, more or less similar, or not similar? This second approach analyzes the viability of the African Union’s project.

The paper is organized as followed: the section 2 presents the literature review. The sections 3 and 4 present the methodology and the results.

2. A Brief Literature Review

The international economic shock impacts in Africa had been analyzed by many recent studies. Kose and Riezman (2001) studied the impact of international trade shocks in African economies modeled by the relationship between the fluctuations in the prices of exported primary commodities, imported capital goods, intermediate inputs, the world real interest rate and macroeconomic fluctuations in Africa. Their results suggest that “while trade shocks account for roughly 45 percent of economic fluctuations in aggregate output, financial shocks play only a minor role. Adverse trade shocks induce also prolonged recessions.” Nkomo (2006) studied the relationship between world oil price movements, energy and development on Southern African countries. His result suggests that “oil price shocks increase the total import bill for a country. Low-income countries and poorer households tend to suffer the largest impact from oil price rise”. Berman and Matin (2009) argue that an international industrial crisis would have a big impact on African economies because the growth and development of these economies depend on the export of raw materials.

Concerning the viability of an economic and monetary union creation in Africa and a unified currency, the existing studies analyze in general the optimality of the different areas that belong to

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this continent. We have retained two studies that analyze the viability of a monetary union in the East Africa Community (Buigut, 2004 ; Kishor et al. 2009). The first uses a model of government finance and the second analyzes the correlations of business cycles between countries that compose this community to study her optimality. Coulibaly and Gnimassoun (2012) study the viability of a monetary union in West Africa using a model based on the convergence and co-movements between exchange rate misalignments. Contrary to those studies, Lucas et al. (2011) take into account the external shocks in their analysis. They aim to show whether a monetary union between economies of the Common Market for Eastern and Southern Africa (COMESA) is viable using the responses of the countries that belong to this area to the internal and external shocks, and they conclude that there is a possibility of creating a monetary union there.

3. Impact of international shocks in Africa: a SVAR Model

3.1. The variables

Any national’s VAR is a model with nine variables: three externs and six domestics. External variables represent three types of crises that have affected advanced economies in recent years:

- International monetary shocks: world interest rate is approximated by the Federal funds effective rate (Gossé and Guillumin, 2010);

- International price shocks: we use the world price of oil to characterize this type of shock (Allegret and Sand-Zantman, 2010), because African’s countries produce essentially raw materials (Madley, 2003);

- International income shocks: we approximate international income shock by GDP per capita in OECD countries because this indicator takes into account the population and because it “is a generic measure of economic performance and gives a fairly good indication of the magnitude of the impact of external shocks on the domestic economy” (BAD, 2009).

Domestic GDP per capita represents the endogenous variable. We use the usual determinants of economic growth in a country to characterize the control variables: education (adult literacy rate), investment, life expectancy, public spending and domestic consumer prices.

3.2. Model specification

Our formalization uses a SVAR model to study the impact of external shocks in domestic economy, Gossé and Guilliaumin (2010).

First, we assume that any African’s economy is described by this reduced-form VAR model:

( )

( )

Where

( )

is a matrix polynomial in lag operator L, E

(

)

, Var

(

)

and

( )

, with

, the first derivative, and r, baril, ddgdpocde1, gdp, inv, life, g, p represent respectively, Federal funds effective rate, world price of oil, GDP per capita in OECD, domestic GDP per capita, adult literacy rate, investment, life expectancy, public spending and domestic consumer prices.

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We can rewrite the equation (1) in VMA form:

( )

( )

With

, where

(

)

; an orthogonal normalized innovations vector and represents the structural shocks.

represent respectively the external shocks, the domestic GDP per capita shock, the education shock, the investment shock, the sanitary shock, the public spending shock and the domestic consumer prices shock, satisfying

and

(

)

, with I the identity matrix.

The consequence is that

. Using the orthogonal matrix S, we can write the VMA model with structural shocks:

( )

( )

Were

( ) ( )

.

If we compare the number of parameters that we must determine to identify the VAR structural model and the numbers of parameters effectively estimated in the VAR model, we conclude that the identification of the VAR structural form conduces to impose ( ) constraints.

We assume that the external variables are exogenous, relatively to domestic variables (Allégret and Sand-Zantman, 2007; Gimet, 2007; Sato and al. 2009).

Thus, we study the contribution of international shocks to the variance of endogenous variable using a SVAR model with an exogenous hypothesis, Mackowiak (2007). This specification improves the quality of the estimations (Sosa, 2008). We rewrite de SVAR model in this form:

[

( ) ( ) ( ) ( )

] [

( ) ( )

]

( ) ( )

Where

for any

, with

[ ( )

]

and

[ ( ) ( )

]

, with I the identity matrix. ( ),

( ),

( )

and

( )

represent respectively, the

vector of external variables, the vector of domestic variables, the vector of structural external shocks and the vector of structural domestic shocks. We assume with Gossé and Guilliaumin (2010) that

( )

for any

. That is to say that the domestic structural shocks do not affect ( ) in t or in

. We also suppose that a short-term shock of any external variable do not

affects any others external variables (Sato and al. 2009).

3.3.Data characteristics

The data used in this study come from the websites of the World Bank and the United States Federal Reserve. We use ADF and Fhillips-Perron tests to study the stationarity of the series, before using the short-run SVAR (there is no long-term relationship between the variables). In applying this model, the Akaike Information Criterion (AIC) is used to determine the optimal lag length. After the estimations, we perform the residual autocorrelation test (LM test), collinearity test (Wald test), and we also check the stability of the model. The model was estimated using Stata 10.0 during 1970-2007.

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5 4.

Results

4.1. International income shocks

OEDC GDP per capita shocks impact 12 African countries: Benin, South Africa, Botswana, Chad, Ghana, Kenya, Mali, Niger, Centrafrique, Senegal, Togo and Tunisia. A 1% decrease in OEDC GDP per capita affects each country from -0.23 to -0.09 %. Inversely a 1% increase affects each country from 0.1 to 0.16%.

Let us analyze the impulse response functions. Appendix 2.1 presents the summary of impulse response functions of the endogenous variable to the positive OEDC GDP per capita shocks. The graphs indicate in general that the responses seem to be more or less similar except for the Chad and Ghana. Positive OEDC GDP per capita shock has initially a positive effect on GDP per capita in each country but after one period it becomes negative and dies out after 4 or 5 years.

4.2. International monetary shocks

Federal funds effective rate shocks impact six African countries: South Africa, Chad, Centrafrique, Kenya, Mali and Senegal. A 1% decrease in federal funds effective rate affects each country from 4.2 to 8.04%. Inversely a 1% increase affects their GDP per capita from -0.66 to -0.46 %, except for South Africa and Kenya for which, a decrease in federal funds effective rate has a negative impact on their GDP per capita, and inversely.

Appendix 2.2 presents the summary of impulse response functions. A positive Federal funds effective rate shock has initially a positive effect on GDP per capita in South Africa and Kenya. This impact becomes negative after 3 years in South Africa and after 4 years in Kenya and dies out. In Mali, a positive Federal funds effective rate shock has initially a negative effect on GDP per capita during the first year, and a positive effect in the second year, a negative in the third year, and dies out after 4 years. The impulse response functions of Chad, Centrafrique and Senegal are more or less similar with the Kenya and South Africa’s impulse response functions.

4.3. International price shocks

World price of oil shocks impact five African countries: South Africa, Algeria, Congo, Nigeria and Tunisia. Except South Africa, all the others countries are oil producers. A 1% decrease in world price of oil affects each country from -0.99% to -0.7. Inversely a 1% increase affects each country from 0.01 to 0.12%, excepting Tunisia for which, a 1% decrease in world price of oil impacts its GDP per capita of 9.94% and a 1% increase of -0.004%.

Appendix 2.3 presents the summary of impulse response functions. Positive world price of oil shock has initially a positive effect on GDP per capita but after one year it becomes negative and dies in general after 2 years, except Tunisia for which a positive world price of oil shock has a negative impact and dies after 5 years.

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5. Conclusion

First of all the contribution of this study is to verify the decoupling or no decoupling African economic conjunctures and international economic shocks. We come up with the response there is no decoupling. We have estimated our SVAR model in 15 African countries.12 countries are exposed to OEDC GDP per capita shocks, six to Federal funds effective rate shocks and five to World price of oil shocks. Secondly, the impulse response functions of the African economies to OEDC GDP per capita shocks seem to be more or less similar. In general, the effect is first positive, becomes negative after one year, and dies out. Concerning the Federal funds effective rate shocks, five countries have approximately the same response, and four in the case of the World price of oil shocks. Based on the response of any African economy to the International income, monetary and price shocks, we can conclude that there is a possibility for African Union to create an economic and monetary union for the African countries and a common currency.

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References

African Development Bank, 2009. Impact of High Oil Prices on African Economics. Working paper. Allegret, J-P., Sand-Zantman, A., 2010. Processus d’intégration et coordination des politiques macroéconomiques dans le MERCOSUR: une approche en termes de cycles. L’actualité économique, Revue d’analyse économique, vol.86, n°2.

Berman, N., Martin, P., 2012. The vulnerability of sub-Sahara Africa to the financial crisis: the case of trade. IMF Economic Review, Vol. 60, Issue 3, pp. 329-364, 2012.

Buigut, S., 2004. Seigniorage and the Proposed East Africa Community (EAC) Monetary Union. The African Finance Journal, vol. 6, issue 2, pages 36-46.

Congressional Research Service, 2010. The Global Economic Crisis: Impact on Sub-Saharan Africa and Global Policy Responses. Working paper prepared for members and Committees of Congress, April. Coulibaly, I., Gnimassoun, B., 2012. Optimality of a monetary union: New evidence from exchange rate misalignments in West Africa. Economix Working Paper 2012-37.

Gimet, C., 2007. L’impact des chocs externes dans les économies du Mercosur: un modèle VAR structurel. Economie Internationale, 110, pp.107-136. 7.

Gossé, J-B., Guillaumin, C., 2010. L’impact des chocs externes sur et dans la zone euro: un modèle VAR structurel. Economie & prévision N° 195-196.

International Monetary Fund, 2010. The implications of the global financial crisis for low-income countries. Washington, March.

Kishor, Kundan, N., Ssozi, J., 2009. Is the East African Community an Optimum Currency Area? MPRA Paper N°17645.

Kose, M. A., Riezman, R., 2001. Trade shocks and Macroeconomic Fluctuations in Africa. Journal of Development Economics, vol.65, pages: 55-80.

Lucas, K. N., Opolot, J., Abuka, C., Apaa-Okello, J., 2011. Nature and Extent of Shocks in COMESA: Implications for a Monetary Union. Interdisciplinary Journal of Research in Business, vol.1, pp. 23-46. Madley, J., 2003. Transnational Corporations and Developing Countries: big Business, Poor peoples. The ACP-EU Courier, (196): 36-38.

Mackowiak, B., 2007. External shocks, U.S. monetary policy and macroeconomic fluctuation in emerging markets. Journal of Monetary Economics, vol.54, pp.2512-2520.

Nkomo, J-C., 2006. The Impact of higher oil prices on Southern African countries. Journal of Energy in Southern Africa, Vol. 17 N°1.

Sato, K., Zhang, Z., McAleer, M., 2011. Identifying Shocks in Regionally Integrated East Asian Economics with Structural VAR and Block Exogeneity. Journal Mathematics and Computers in Simulation, Volume 81 Issue 7, March, pages 1353-1364.

Sosa, S., 2008. External Shocks and Business Cycle Fluctuations in Mexico: How Impact are U.S. Factors. IMF working paper 08/100.

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Appendix:

Appendix 1: Model estimations

*, ** and ***: significant at 10%, 5% and 3%. We represent the negative effect and the Cholesky decomposition value (positive effect).

Afrique du Sud Alegria Bénin Botswana

gdp ocde -0,13*** (-2,72) 0,02 -0,1 (-1,25) 0,01 -0,14*** (-2,24) 0,015 -0,21*** (-4,11) 0,021 baril -0,7*** (-2,63) 0,08 -0,76*** (-2,54) 0,05 0,14 (0,44) -0,029 -0,204 (-0,56) 0,034 r -3,9* (-1,64) 0,55 -2,59 (-0,82) 0,44 1,39 (0,46) -0,156 -3,09 (-0,95) 0,361 life 0,001 (0,1) 0,001 -0,03*** (-2,08) 0,002 0,02* (1,88) -0,001 -0,03 (-1,37) 0,003 alph -0,002 (-1,52) 0,000 0,03*** (2,15) -0,002 0,01 (0,78) -0,001 -0,002 (-0,36) 0,001 inv -0,1 (-0,83) 0,015 0,12 (0,62) -0,015 -9,28* (1,83) 0,728 0,047 (0,18) 0,018 p 1,8*** (4,12) -0,08 0,48 (0,4) -0,098 3,11*** (2,84) -2,04 -0,48 (-1,49) 0,025 g 0,02 (0,31) -0,01 -0,17 (-1,37) -0,004 0,06 (0,51) -0,001 0,15 (0,95) -0,009

Centrafrique Congo Ghana Kenya

gdp ocde -1,14*** (-2,51) 0,02 -0,05 (-1,02) 0,007 -0,19*** (-3,4) 0,023 -0,15*** (-2,79) 0,018 baril 0,04 (0,15) -0,004 -0,99*** (-5,25) 0,125 0,4 (1,33) -0,05 -0,33 (-1,04) 0,024 r 5,55*** (2,15) -0,004 -2,66 (-0,94) 0,555 -3,29 (-1,33) 0,252 -5,43*** (-2,08) 0,508 life -0,005 (-0,32) 0,002 -0,00 (-0,00) 0,001 -0,032*** (-3) 0,001 -0,009 (-0,6) -0,000 alph 0,02 (1,08) -0,001 -0,003 (-0,81) -0,000 -0,03 (-1,46) 0,002 -0,001 (-0,11) 0,000 inv -0,13 (-0,38) -0,003 0,37 (1,55) -0,06 -0,04 (-0,1) -0,04 -0,07 (-0,36) 0,029 p -0,66 (-0,06) 0,286 -1,23 (-1,11) -0,5 (-0,48) -0,05 1,51 (1,46) -0,2 g 0,167 (0,62) -0,002 0,41** (1,93) -0,089 -0,28** (-2,01) 0,005 0,13** (1,94) -0,009

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Mali Niger Nigéria Sénégal

gdp ocde -0,13*** (-2,6) 0,018 -0,23*** (-6,77) 0,031 -0,04 (-0,75) 0,005 -0,18*** (-3,94) 0,023 baril -0,181 (-0,72) 0,015 0,53 (1,48) -0,029 -0,84*** (-4,141) 0,104 -0,02 (-0,07) -0,015 r 4,38** (1,97) -0,462 1,56 (0,51) -0,183 0,66 (0,24) 0,151 8,03*** (3,14) -0,662 life -0,02* (-1,8) 0,003 -0,004 (-0,18) -0,001 -0,01 (-0,98) 0,002 -0,002 (-0,13) 0,001 alph -0,13*** (-2,09) 0,013 -0,047 (-0,61) 0,005 -0,006 (-0,51) 0,001 0,01 (0,29) 0,002 inv 0,12 (0,85) -0,013 -0,98 (-1,48) 0,089 -0,14 (-0,78) -0,043 0,16 (0,98) -0,011 p 2,21*** (2,44) -1,71 -1,5 (-1,11) -0,405 0,87 (0,77) -0,192 5,04*** (6,77) -2,14 g 0,13 (0,84) -0,002 0,46*** (2,61) -0,04 0,68*** (2,87) -0,037 0,13 (1,2) -0,013

Tchad Togo Tunisie

gdp ocde -0,08* (-1,69) 0,011 -0,23*** (-4,92) 0,029 -0,41*** (-6,07) 0,031 baril 0,19 (0,81) -0,03 -0,03 (-0,08) -0,008 -0,85 (-1,34) -0,004 r 4,5*** (2,25) -0,539 1,25 (0,39) -0,07 9,95** (1,95) -0,409 life -0,05*** (3,95) 0,005 -0,01 (-0,91) 0,002 0,004 (0,22) -0,001 alph 0,01 (1,11) -0,002 -0,003 (-0,72) 0,000 0,003 (0,22) 0,001 inv -0,66* (-1,87) 0,067 0,17 (0,47) 0,09 -0,13 (-0,4) -0,009 p -2,44** (-1,9) 1,858 -1,66 (-1,24) 0,63 0,021 (0,01) g 0,089 (0,27) 0,01 0,77*** (3,79) -0,037 0,32 (3,14) -0,001

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Appendix 2. Impulse response functions

Appendix 2.1. International income shocks

Benin South Africa Botswana

Ghana Niger Togo

Chad Kenya Mali

Centrafrique Senegal Tunisia

-.05 0 .05 .1

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04 .06 0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonal ized i rf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonal ized i rf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04 .06 0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonal ized i rf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05 .1

0 5 10

test2, ddgdpocde1, ddpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.04 -.02 0 .02 .04 0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05 .1

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04 .06 0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05 .1

0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.01 0 .01 .02 .03 0 5 10

test2, ddgdpocde1, dpib1

95% CI orthogonalized irf step

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Appendix 2.2. International monetary shocks

South Africa Chad Kenya

Mali Centrafrique Senegal

Appendix 2.3. International price shocks

Congo South Africa Algeria

Nigeria Tunisia -.04 -.02 0 .02 .04 0 5 10

test2, dfed, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05

0 5 10

test2, dfed, ddpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04 .06 0 5 10

test2, dfed, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05

0 5 10

test2, dfed, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04 .06 0 5 10

test2, dfed, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05

0 5 10

test2, dfed, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05 .1

0 5 10

test2, dbaril, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.04 -.02 0 .02 .04 0 5 10

test2, dbaril, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.02 0 .02 .04

0 5 10

test2, dbaril, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.05 0 .05 .1

0 5 10

test2, dbaril, dpib1

95% CI orthogonalized irf step

Graphs by irfname, impulse variable, and response variable

-.04 -.02 0 .02

0 5 10

test2, dbaril, dpib1

95% CI orthogonalized irf step

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