Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 The Impact of Exports on Economic Growth in Botswana 1980-2013 Letlhogonolo M. Mpatane and Ireen Choga The objective of this paper was to determine the impact of exports on economic growth in Botswana using data from 1980 to 2013. The study tests for stationarity in variables (GDP, exports, exchange rate, degree of trade openness and terms of trade) using the Augmented Dicky-Fuller test (ADF). Cointegration test is done using the Johansen (1991, 1995) methodology. The Vector Error Correction Model is run to measure the correction from disequilibrium of previous periods. Exports and real exchange rate have been found to have a positive long-run relationship with economic growth. The estimate of the speed of adjustment coefficient found in this study has revealed that about 68 percent of the variation in GDP from its equilibrium level is corrected within one year. The results are favourably comparable to those in the literature and are also supported by previous studies. Keywords: Exports, Economic Growth, Vector Autoregression, Botswana. 1. Introduction Botswana is a landlocked country located in Southern Africa and shares its boarders with Zimbabwe, Zambia, South Africa and Namibia. Botswana got its independence on the 30th September 1966. According to Beaulier (2003), Botswana was one the poorest countries when it gained its independence from the United Kingdom in 1966 and it has since transformed itself and has become one of the fastest growing economies in the world. According to Sentsho (2003), before Botswana got its independence, its main export was mainly beef and its trade was dominated by game meat and game skins. Botswana continued to export beef and relied on beef export for its economic growth until after its independence when it started discovering minerals. In 1967, diamond was discovered at Orapa and started its first production in 1971 while the Jwaneng pipe was discovered in 1972 and began with production in 1982. Several discoveries of high grade copper were made at Thakadu, Makala and Bushman in the Matsitama Schist Belt in the 20th century with the most recent exploration work done by Bamagwato Concessions Limited (BCL) between 1957 and 1974 and Falconbridge between 1977 and 1989. Other minerals such as nickel, matte and coal were also discovered. ______________________ Letlhogonolo M. Mpatane, School of Economic & Decision Sciences, North West University, South Africa, Email: lettieatty@gmail.com Dr Ireen Choga, School of Economic & Decision Sciences, North West University, South Africa, Email: Ireen.Choga@nwu.ac.za Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 Up to about 1990, Botswana used to export 90% of its products to the world market beyond Africa, mainly to Europe and America. Botswana forms a customs union with South Africa Namibia, Zimbabwe and Zambia. Botswana experienced rapid economic growth rate for more than three decades which is associated with its minerals more especially diamond. According to (Limi, 2006), rich resource-countries tend to grow less rapidly than scares resources-countries which he referred to as the resource curse. In this case, Botswana contradicts the resources curse as it managed to transform diamond into growth and development. This was supported by Sentsho (2003) who stated that if exports from primary resources are managed properly they can lead to a sustained economic growth. Another factor apart from diamond that made it possible for Botswana to have a high economic growth over the period is the country’s exchange rate policy. Botswana used the South African Rand before and after it gained its independence in 1966. It was a member of Rand Monetary Area (RMA) until1976 when it terminated its membership and formulated its own central bank with Pula as its currency (Harvey 1996; Ahmed, 2006). This resulted from the fact that the membership of RMA did not give Botswana monetary and exchange rate independence as the policies were managed by the South African Reserve Bank. The establishment of a reserve bank by Botswana gave it the opportunity to formulate its own monetary and exchange rate policies that best suit its exports, economic growth and development. The paper is organised as follows: Following this introduction (Section 1), Section 2 provides a brief overview of exports and economic growth in Botswana over the period 1980-2013. This will be followed by Section 3 which provides review of related theoretical and empirical literature. After literature review follows presentation of methodological framework and sources and data in Section 4. Section 5 will cover estimates of the regression and analysis of results. Lastly policy implications, recommendations and conclusion will be presented in Section 6. 2. An Overview of Exports and Economic Growth in Botswana Botswana adopted the Export-Led Strategy during the colonial era (1885-1966) when it was Bechuanaland Protectorate (Sentsho 2003). Export-Led Strategy is an economic development strategy in which export expansion play a central role in a country’s economic growth. Statistical evidence has shown that exports have played a very important role in the economic growth of Botswana by contributing more than 50% towards the country’s GDP. Historical economic activity shows that at independence, 40% of the country’s GDP and 90% of employment were mainly from the agricultural sector. As more minerals were discovered, the agricultural sector contributions declined over the years to a point where it contributed 4% and 6% by the mid-1990s (Beaulier (2003). The mining sector, especially the diamond sector has been the main contributing factor to the country’s economic activity since the early 1990s to date. Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 The previous efforts to diversify have been slow and largely unsuccessful. The NDP10 has identified tourism, international financial services, energy (including regional power export), agriculture and manufacturing as the main potential sectors for diversification. Botswana also has copper, nickel, coal, clay, soda ash, salt and small quantities of gold. This will provide initial diversification from diamonds to other minerals and eventually to non-minerals (ADF, 2009). The global financial and economic crisis of 2008-2009 hit Botswana very hard. Global diamond sales fell sharply and led to a negative real growth rate. The temporary closure of the diamond mines in the first half of 2009 caused the economy to fall into a recession with a growth rate of minus 7.8 percent in 2009as well as budget and balance of payments deficit (De Beers Family of Companies, 2009). The non-mining sector on the other hand continued to grow steadily at 9.7 percent and 7.5 percent in 2011 and 2012 respectively. The economy recovered in 2010 as a recovery on diamond production helped to lift overall GDP by 8.6 percent for that year. The GDP then fell to 6.1 percent in 2011. In 2012, 8.1 percent contraction in the mining output lead to a 3% increase in growth. Expotrs percentages Figure 1: Exports Contribution to GDP in Percentages 80 70 60 50 40 30 20 10 0 Exports Contribution to GDP in percentages Years Exports as percentage of GDP Source: World Bank 2014 The export of goods and services as a percentage of GDP in figure 1 shows that exports have been the main contributor to Botswana`s economic growth. The share of exports towards GDP rose from 1982 up until 1985 when exports contributed 70 percent of the GDP. In 1982 the Jwaneng Diamond mine started its production. This mine produces the largest output in the country and as a result it led to an increase in total exports. The total export share to GDP then declined to 47 percent in 1993. This was because of a reduction in the sales of Copper Nickel matte and beef. It then fluctuated between 49 and 53 percent in 2008. It then fell to 37 percent in 2009 due to the recession and then inclined to 55 percent in 2013. Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 3. A Review of Supporting Literature This study is supported by several economic theories which include among others Smith, (1776), the Theory of Absolute Advantage, David Ricardo (1817), the Theory of Comparative Advantage, Heckscher (1919) and Ohlin (1924), Heckscher-Ohlin Model (HOM). The Heckscher-Ohlin Model used multiple factors of production. The authors put more emphasis on the roles of labour, capital and land in agriculture and industry trying to show how their inclusion shapes a country pattern of specialisation and trade. However, the modern presentations of this model consider only two factors of production labour and capital. Ohlin (1933) disputed that countries differ in their respective features of labour and capital and that for both goods to be produced they needed different composition of capital and labour. A wide range of empirical studies on the impact of exports on economic growth have been carried out world-wide by different authors and various results were obtained. Due to methods used and data employed, some studies were not able to give supporting facts fulfilling this relationship while others gave evidence that indeed there was a causal linkage between exports and economic growth. However, very few studies have been conducted to explain the exports behaviour in Botswana. Research conducted using time series approach includes the work of Jordaan and Eita (2007) and Abual-Foul (2004). Studies that focused on the impact of exports and economic growth in grouped countries were also discussed and they include Njikam (2003) and Sinoha-Lopete (2004). Although a large gap of literature exists in Botswana, few researchers have conducted a research on the impact of exports and economic growth in Botswana. The researchers include among others Jordaan and Eita (2009) and Sentsho (2002). The next section discusses the methodology used for this study. 4. Methodology used in the Study To estimate the impact of exports on economic growth in Botswana, this study uses Vector Autoregression (VAR) model. . According to Gujarati and Porter (2009), the VAR methodology superficially resembles simultaneous equation modelling where several endogenous variables are considered. The Augmented Dickey-Fuller (ADF) statistic is used to test the stationarity and non-stationarity of the variables and their order of integration. The univariate characteristics is used to show whether the variables are stationary or non-stationary. If the variables are I(1), the next step is to test whether they are cointegrated. The Johansen (1991, 1995) cointegration test is employed followed by vector error correction model (VECM) which is used to estimate the long run equation and the existence of error correction. Diagnostic checks are also performed to test for normality (Jarque-Bera), heteroskedesticity (White test) and serial correlation (Lagrange Multiplier). Lastly stability test is done to check if VAR satisfies stability condition of our model. 5. Model Specification The study adopts and modifies Artha, Irfan and Komal (2012) model which explains economic growth as a function of exports and terms of trade. However, this study adds Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 exchange rate and degree of trade openness which may have a great influence on export-economic growth relationship in Botswana. Artha, Irfan and Komal (2012) model was formulated as: Y f ( X , TOT ……………………………………………………………….1 Where Y was Real GDP, X Real Exports and TOT as Terms of Trade. This model has been modified to: Y f ( X , RER , DTOP , TOT ) ……………………………………………………2 Real exchange rate (RER ) and degree of trade openness (DTOP ) have been added to the model. The study uses annual time series data covering the period1980 to 2013. Data on exports, GDP and DTOP was obtained from Bank of Botswana Annual reports (1980 – 2013) while data on TOT was obtained from the World Bank. All data series were tested for stationary as a way to avoid making conclusion based on statistically spurious results. The tests were done using Augmented Dicky-Fuller Test and the results are presented in Table 1. Table 1: Unit root/Stationarity tests results Augmented DickeyTest Fuller Order of Variable Constant Constant None integration and Trend Level LRGDP -3.789*** -1.849 6.867 1st Diff DLRGDP -7.514*** -9.429*** -1.223 Level LRX -1.3639 -2.174 4.1677 1st Diff Level DLRX LRER -6.102*** -2.303 -6.493*** -1.669 -3.708*** 0.474 1st Diff DLRER -4.774*** -5.0616*** Level 1st Diff LDTOP DLDTOP -2.3299 -6.282*** -2.4627 -6.367*** Level 1st Diff TOT DTOT -2.8729* -3.98*** -2.674 -4.074*** 8.8049*** -2.1644** 6.3515*** -0.0287 4.0228*** Conclusion Stationary Stationary Nonstationary Stationary Nonstationary Stationary stationary stationary *represents a stationary variable at 10% level of significance **represents a stationary variable at 5%, 10% level of significance ***represents a stationary variable at 1%, 5%, 10% level of significance L represents Logarithms of variables D represents differenced variables Table 1 show that LRGDP was stationary both at levels and 1 st difference. All the variables became stationary at 1st difference. The null hypothesis of a unit root is rejected in favour of the stationary alternative in each case if the test statistic is more negative than the critical value. Therefore, a rejection of the null hypothesis means Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 that the series do not have a unit root. The results from the ADF test are in line with those from the graphical analysis. We therefore conclude that the all the variables are I(1) stationary. This means that the variables are integrated of the same order which lead to a cointegration test. Table 2: Johansen cointegration tests results in lag interval of 1 Ho Eigenvalue Trace Critical Max-Eigen Critical Rank=P Statistics value statistics value 0.05 0.05 P=0* 0.740256 95.73236 69.81889 43.13785 33.87687 P≤1* 0.638561 52.59451 47.85613 32.56516 27.58434 P≤2 0.373220 20.02935 29.79707 14.94913 21.13162 P≤3 0.133967 5.080222 15.49471 4.602645 14.26460 P≤4 0.014813 0.477577 3.841466 0.477577 3.841466 Trace test indicates 2 cointegrating equation at the 0.05 level Max-eigenvalue indicates 2 cointegrating equations at the 0.05 level. *denotes rejection of the hypothesis at the 0.05 level Table 2 shows that the trace test and the max-eigenvalue test indicate 2 cointegrating equations at 0.05 levels which mean that we reject the hypothesis zero and one in favour of at least two cointegration vectors. The trace statistics and max-eigenvalue values are greater than the critical values at the 0.05 level with the probability less than five percent. The presence of cointegration between variables suggests a longrun relationship between them. Since cointegration of variables has been established, the vector error correction model of the VAR is now employed. The next section establishes the short-run and long-run dynamics of the model. Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 Cointegrating Eq Table 3 Vector Error Correction Estimates cointEq1 Log_RGDP(-1) 1.000000 Log_RX(-1) -1.069646 (0.00885) [-120.869] -0.103945 (0.01799) [-5.77766] 0.535533 (0.06241) [8.58149 1.213456 (0.10752) [11.2857] -0.715721 Log_RER(-1) Log_DTOP(-1) TOT(-2) c Error Correction CointEq1 D(LOG_RG DP) -0.687292 (0.22277) [-3.08518] R-squared Adj. R-squared 0.770788 0.630715 D(LOG_RX ) -0.036639 (0.52967) [-0.06917] D(LOG_RE R) -0.069403 (0.61636) [-0.11260] D(LOG_DTOP ) 0.108106 (0.41290) [0.26182] 0.487996 0.306090 0.203809 0.175104 -0.117965 -0.282753 D(TOT(-1)) -0.592301 (0.08002) [-7.40173] 0.84448 4 0.74944 6 The Error Correction model shows the long-run and short-run dynamics to be estimated in a single step. The error correction term is expected to be negative and for this model it is -0.687292 which means that it is statistically significant. This also indicates that the dynamics adjust to long-run equilibrium. The speed of adjustment is 68.72%. This is the speed at which our dependent variable GDP returns to equilibrium after a change in an independent variable in this case exports. Our model shows that there is a positive long-run relationship between real exports and real GDP and real exchange rate and real GDP. Both the R-squared and adjusted R-squared are more than 50% which is statistically significant and shows the goodness of fit to the model. The Adjusted R-squared is 0.630715 which is very good. Adjusted R2 is a measure of the closeness of fit in the regression model. After establishing the short-run and long-run dynamics of this model, the next step is to do diagnostic tests. Diagnostic tests are very important in the analysis because if there is a problem in the residuals from the estimation of the model, it means that the model is inefficient such that the parameter estimates from such a model may be biased. To test whether our model is a reasonable fit to the data the diagnostic tests were carried out and they included checking for serial correlation, normality and heteroskedasticity. The tests carried out showed the model is reasonably well specified. The diagnostic test Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 revealed that the residuals are normally distributed, are not serially correlated and that they are homoscedastic. The results obtained from the diagnostic tests are shown in table 4 below. Table 4: Diagnostic checks results Test Null Hypothesis t-Statistic Probability Langrage Multiplier (LM) No serial correlation 19.28 0.783 White (CH-sq) No conditional heteroskedesticity 342.64 0.304 Jarque-Bera (JB) There is a normal distribution 2.059 0.357 Table 5 Stability Test Roots of Characteristic Polynomial Endogenous variables: LOG_RGDP LOG_RX LOG_RER LOG_DTOP TOT Exogenous variables: C Lag specification: 1 2 Date: 11/07/14 Time: 14:05 Root Modulus 0.989394 0.989394 0.752706 0.565616 0.384167i 0.565616 + 0.384167i 0.752706 0.682565 0.132981 0.565928i 0.132981 + 0.565928i 0.682565 -0.556105 0.556105 -0.256013 0.256013 0.124723 0.124723 0.683744 0.683744 0.581342 0.581342 No root lies outside the unit circle. VAR satisfies the stability condition. Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 Figure 2 Stability test Inverse Roots of AR Characteristic Polynomial 1.5 1.0 0.5 0.0 -0.5 -1.0 -1.5 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 Table 5 and figure 2 above show that no root lies outside the unit circle. VAR satisfies the stability condition of our model. 6. Policy Implications, Recommendations and Conclusions In determining the impact of exports on economic growth in Botswana, the results obtained revealed that there is a long-run positive relationship between exports and economic growth and between real exchange rate and economic growth. The policy implication of this positive relationship between exports and economic growth in Botswana is that an expansion of exports will lead to an increase in economic growth. This also implies that policy makers in Botswana should continue to promote and implement policies aimed at expanding exports in order to accelerate economic growth and development. The diversification of exports sector away from primary commodities especially diamond should highly be taken into consideration. Botswana can also expand its limited domestic market by exporting more in order to increase economic growth. The exchange rate on the other hand must be kept stable in order to maintain good economic performance as movements on the exchange rate might have negative impacts on the export sector and economic growth. The main objective of this study was to determine the impact of exports on economic growth in Botswana using annual data for the 1980 to 2013. Time series techniques were used to test for the causal relationship between exports and GDP in Botswana. The unit root tests (ADF), a cointegration test (johansen procedure), vector error correction model and diagnostic test were applied. The results of the unit root tests indicated that all variables (LRGDP, LX, LREX, TOT, LDTOP) were stationary in first difference I(1). Since all the variables were stationary and cointegrated of the same order, the Johansen cointegration test was applied and there was evidence of two cointegrating vectors. Long-run exists between exports and economic growth and between real exchange rate and economic growth in Botswana. The Vector Error Correction Model was then conducted. The VECM provided the Proceedings of 32nd International Business Research Conference 23 - 25 November, 2015, Rendezvous Hotel, Melbourne, Australia ISBN: 978-1-922069-89-4 parameter estimates for the long-run relationship. Real Exports and real exchange rate have a positive long-run relationship with real GDP. The speed of adjustment coefficient was -0.687292. 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