Exchange Rate Pass-Through in Nigeria

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Exchange Rate Pass-Through in Nigeria A paper submitted for presentation at the Canadian Economic Association (CEA) 0 th Annual Meetings, May 6-8 th 006, Concordia University, Montreal (Quebec) By Abstract Olajide.S. Oladipo Economics Department University of Birmingham Edgbaston Park Road Birmingham B15 TT United Kingdom E-mail: oladipojide@yahoo.com Exchange rate pass-through is the phenomenon whereby changes in the value of foreign exchange are reflected in domestic price of imports. Thus, the paper examines exchange rate pass-through for Nigeria imports is by applying an econometric procedure which avoids the pit-falls in previous studies to aggregate data. We provide estimates of passthrough based on Johansen technique. We found incomplete pass-through for Nigeria. JEL Classification Numbers: D1, E31, F1 Keywords: Pass-through, exchange rate, import prices

Exchange Rate Pass-Through in Nigeria 1. Introduction The degree to which exchange rate movements are reflected in prices has long been a question of interest in international economics. Interest in this issue, however, was rekindled in the 1970s by a combination of rising inflation and the adoption of more flexible exchange rate regimes in many industrialized countries following the demise of the Bretton-Woods system of adjustable pegs. Also, fluctuations in the exchange rate have been prominent in developing countries with the adoption of the International Monetary Fund (IMF) and the World Bank adjustment programmes 1. As a result, a number of authors have been motivated to examine more closely the relationship between exchange rates and prices of internationally traded goods, refer to as exchange rate pass-through. The exchange rate pass-through is the degree to which exchange rate changes are reflected in the destination currency prices of traded goods, Menon (1996). As revealed from the exchange rate pass-through literature, most empirical studies on pass-through focused on large open economy such as the US, the UK, Japan, Germany, and France. In fact, about 55 percent of all pass-through studies until 1995 concentrated on the United States. Thus, little attention has been given to the effects of the movements of the exchanges rates on import and domestic prices in small open economies in developing countries, particularly in Africa. Fist, this study tries to redress the imbalance in country study coverage by presenting estimates of the effects of changes in the exchange rate on domestic price of imports in Nigeria. Second, most researchers have ignored the time series properties of the data in conducting their estimation. Given the fact that the data used to estimate pass-through are usually trended, pass-through estimates from these studies may have been biased due to non-stationarity of the data, but in this study, an up-to-date econometric method is 1 The effectiveness of the exchange rate policy depends crucially on the nature and timing of linkages between nominal exchange rate, prices and inflation.

used. Finally, we employed aggregate data to reveal the overall affect of movement in exchange rate on domestic prices of imports within the Nigerian economy. In addition to this introductory part, this paper contains six other sections. The second section focuses on the theory of exchange rate pass-through. Section three contains the review of literature, while the empirical model, data construction and sources, and econometric procedure are laid out in section four. Section five contains the results while the last section contains concluding remarks.. The Theory of Exchange Rate Pass-Through: Market Structure and Product Characteristics In a perfectly competitive market there is no deviation between price and marginal cost. Therefore, when market structure deviates from perfect competition to imperfect competition, pricing will no longer be at marginal cost, and firms can charge a mark-up on costs to earn above normal profits even in the long run. However, the variation in mark-up over marginal cost will be determined by the degree of substitutability between domestic and imported goods, as determined by the degree of product differentiation and the degree of market integration or segregation. A market is integrated when geographical or nationality does not have systematic effects on transaction prices for identical products while segregation refers to lack of integration. A product market is geographically segmented if the location of the buyers and sellers influences the terms of the transaction in a substantial way 3. According to Pigou (190) there exists third-degree price discrimination. This occurs when different groups of consumers pay different prices for identical goods. However, a market that is integrated may not be perfectly competitive. A monopoly supplier may charge a price above marginal cost, but be incapable of price discrimination if buyers are well organised or the product is easily transported across markets. Specifically, the market for Gold, the location of buyers and sellers is virtually irrelevant to the terms of transaction. 3 The market for Automobile is segmented. Automobiles purchase in foreign market may attract additional taxes at the border and may not comply with safety and environmental regulations in the home market. See Goldberg and Knetter (1997) for details. 3

Therefore, the lower the degree of substitutability between goods and the degree of market integration, then, the greater will be the market power of the sellers. Following from the above, most recent research work on pass-through has employed the mark-up approach. Thus, in this paper, we employed mark-up model to derive the import price equation that is used to test for the effects of pass-through for domestic price of imports in Nigeria. 3. Literature Review Our observation, based on the findings from the empirical literature on pass-through revealed that cases of incomplete pass-through are common phenomenon in most countries, but with exception of few 5. However, the degree of pass-through seems to be quite different across countries and products. Factors that may have influenced the degree of pass-through are the openness and the size of the country. A close observation revealed that different results for a country, especially for the United State, stem primarily from the use of different methodology, model specification and variable selection rather than from different time periods studied. For the small open economy, which is the focus of this study, findings from previous studies seem mixed incomplete and complete exchange rate passthrough. Evidence of incomplete pass-through abounds in studies by Lattimore (1988), Phillips (1991), Menon (1993, 1995) for Australia; Moreno (1989) for Taiwan and Korea, Athukorala (1991) for Korea; Athukorala and Menon (199) and Alexius (1997) for Sweden, while recent studies by Kenny and McGettigan (1996, 1998) for Ireland and Kikuchi and Sumner (00) found almost complete pass-through. Menon (1993, 1995 and 1996), Papell (199), Kenny and McGettugan (1996), Feenstra and Gagnon (1996), Alexius (1997), Goldberg and Knetter (1997), Rezitis and Brown (1999), Ahmad and Ali (1999),and Hyder and Shah (00). 5 Pass-through is complete when mark-ups of prices over cost are constant or marginal costs are constant. Of course, incomplete pass-through may be due to a pricing strategy often employed by exporting firms, a phenomenon termed as pricing to- market. So, rather than constantly adjusting prices to exchange rate changes, an exporting firm may choose to hold the price constant and simply reduce or increase the markup on prices. This implies that exporting firms accept temporal losses in their revenue in order to avoid long run losses (in case of an appreciation of the own currency) of their market share.

The Empirical Model, Data Construction and Sources and Econometric Procedure.1 The Empirical Model As earlier mentioned, most previous studies have employed import price equation derived within the mark-up framework to measure pass-through. Of course, manufactured goods are typically differentiated and traded in markets that are characterised by imperfect competition; thus, the mark-up model seems more appropriate for our study. We assume that foreigners set their foreign currency export price, PX, as a mark-up, π, on their production cost in foreign currency, CP 6 : PX = π CP Equation 1 The domestic currency (i.e. the Nigerian naira) import price is, therefore, given by: PM = PX ER = ( π CP)ER Equation where ER is the exchange rate defined as the domestic currency price of one unit of foreign currency. The profit mark-up is hypothesized to depend on competitive pressures in the domestic market, and the exchange rate. This competitive pressure is proxied by the gap between the price of import-competing goods, PD, and the exporter s production cost. The influence of domestic demand condition on the import pricing decision is also captured by PD. Accordingly, the profit mark-up is thus modeled as: α PD π = CP ER Thus, substituting equation 3 into equation we obtain: α Equation 3 PD PM = ( CP ER) Equation CP ER Therefore, taking natural logarithms of the variables, equation can be reformulated as; LPM = αlpd + ( 1 α ) LCP + ( 1 α )LER Equation 5 The model above implies a rate of pass-through that is equal in magnitude for changes in foreign costs and the exchange rate 7.. Data Construction and Sources 6 The mark-up is equal to 1+ λ, where λ is the profit margin. 7 The coefficient of pd which is α, is the complement of the coefficient of both cp and er. Thus, the cross-coefficient restrictions implied by the model suggest that pd has no (full) effect in determining import prices if pass-through is complete (zero). 5

During the data collection, the author noticed that many countries, including Nigeria, with exception of few developed countries 8, do not collect price data for imports and exports, therefore, import unit values are used 9. The study relied on secondary data, basically, quarterly time series data from 1970:1 to 001:. This gives a sample size of 18 observations. The sample size is relatively large when compared with sample size in previous studies on pass-through, particularly for small open economies. The import unit values for Nigeria imports were collected from the African Development Indicators, a publication of the World Bank and the Central Bank of Nigeria (CBN). Instead of constructing import unit values for Nigeria for imports from the United States, the United Kingdom, France, Germany, Italy, Netherlands, China and Japan, the major trading partners, we used the total import unit values 10. However, we are justified due to the fact that aggregate imports from these major trading partners constitute, on average, between 67 percent and 85 percent of Nigeria s aggregate total import between 1970 and 001 11. Next, the domestic Nigeria competing price is the Producer Price Index (PPI), is obtained from the World Bank s African Development Indicators and the CBN. This index is derived from price indices for both outputs of manufacturing and agricultural industries. Most previous studies employed a world price variable (in the form of import-weighted export prices) to capture changes in competitiveness of export sales to destination markets. The problem with this index is that it represents the pricing decision on exports to all markets, it is particularly inappropriate for small countries and when pricing to market behaviour are common for manufactures. Thus, to avoid these problems, we construct the foreign cost of production index that is unaffected by the pricing to market problem. The foreign cost of production index is 8 These countries include the United States, the United Kingdom, Japan, and Germany. 9 By definition, the unit values are the values of imports or exports divided by the number of items shipped. However while the problem identify with import unit values as rightly posited by Alterman (1991) are recognised, the import unit values are considered to provide only and best source of data relevant for this study. 10 Though import unit values for Nigeria would have been constructed for the main trading partners but the author was unable to collect volume data for export into Nigeria, while the dollar values of exports are available in Direction of Trade Statistics, a publication of the IMF. 11 The author complied the import share of Nigeria trading partners from the Direction of Trade Statistics and OECD Statistics of Foreign Trade (series A). 6

constructed as an import share weighted-average of foreign costs in the eight major import supplying countries mentioned above 1. Finally, the data for the exchange rates were obtained from the International Financial Statistics (IMF) CD-Rom for all Nigeria s trading partners and convert dollars values to naira, Nigeria s local currency. Thus, we construct the effective or trade weighted exchange rate for Nigeria. This is the weighted average of nominal exchange rates (per foreign currency) of the eight main import supplying countries. The weights used are import share of 1990 13..3 Econometric Procedure In most conventional studies, Ordinary Least Square (OLS) is used. The literature on passthrough revealed that different econometric approach has been used to estimate passthrough with series of short-comings. However, in this study, we use the Johansen procedure. This econometric approach appears most suitable for our estimation. This procedure is a multivariate estimation technique that uncovers long-run stationary relationships among sets of non-stationary data. The multivariate approach, with its allowance for the potential endogeneity of all the variables of interest, eliminates the singleequation bias, which would have been problematic for previous studies on pass-through. Furthermore, the approach allows users to investigate the speed of adjustment to the longrun equilibrium, along with any short-run relationships, which may exist. The first stage of the Johansen procedure involves carrying out a unit root tests on all the variables of interest. By definition, a time series is said to be stationary if its means, variance and covariances are all invariant with respect to time 1. There are several ways of testing for the presence of a unit root but we employed Augmented Dickey Fuller (ADF) and Phillip and Perron (1988) tests. However, the unit root tests suggested by 1 These include the unit labour costs in manufacturing obtained from organisation for economic cooperation and development (OECD), Main Economic Indicators; OECD average import price of crude oil obtained from OECD Economic Outlook; and the price index of minerals, ores and metals were obtained from the International Energy Agency publications. 13 The countries are the United States, the United Kingdom, France, Germany, Italy, Japan, China, and Netherlands and the weights (in percentages) are 11.09, 17.17, 9.16, 15.0,.51, 5.97, 3.3, and.81, respectively. 1 This implies that a stationary series tends to return to its mean value and fluctuate around it within a more or less constant range, while a non-stationary series has a different mean at different points in time and its variance increases with the sample size. 7

Phillips and Perron have two main advantages over the corresponding ADF test. First, in contrast to ADF test, which includes more explanatory variables to deal with the autocorrelated residuals and reduces the effective number of observation, i.e. the degree of freedom, the Phillips and Perron tests overcomes the problem of autocorrelation by using non-parametric correction. Second, the Phillips and Perron test is valid under more general assumptions about the sequence of innovations, hence, allowing for all finite ARMA processes. On the other hand, one of the drawbacks of Phillips and Perron unit root test is that the number of autocovariances used for the Newey-West estimator of the error term variances is arbitrary. Thus, we investigate the stationarity of the variables using both Phillips-Perron and Augmented Dickey-Fuller tests. Therefore, having found that our variables possess a single unit root, we test for cointegration. The number of co-integrating vector ( r ), which indicates the dimension of the co-integrating space, is determined by two tests statistics, maximal eigenvalue ( λ max ) and trace: λ max = N ln 1 λr+1 and m Trace = N ln 1 λ i i= r+ 1 where N is the number of observation and λ the estimated eigenvalue. 5. The Estimation Results As we can see in table 1, the results of unit root tests indicates that we cannot reject the null hypothesis of a unit root at 5% level of significant for the logarithms of the levels of import unit values, producers costs, domestic competing costs and the trade-weighted exchange rate. However, we can reject the null hypothesis of a unit root at 5% significant level for the first difference of all the variables. Thus, the fact that the levels have unit root and the first difference of the series is stationary provides evidence that all logarithms of the series are integrated of order one, i.e. I( 1) 15. 15 Note, with the exception of logarithms level of domestic competing costs. 8

Table 1: Time Series Properties of the Data Variables ADF PP Order of Integration T, C C N T, C C N LPM -.05-1.6.33 -.61 -.6.71 1 LPM LPD -5.5** -.6-5.3** 0.09 -.56**.03-11.19** -1.38-11.01** -0.60-10.35** 3.98 1 LPD LCP -3.19* -3.35* -3.** -3.85** -.33** 1.57-10.7** -3.38* -10.9** -5.56** -8.15** 3.50 1 LCP LER -.08** -1.51-3.39** -1.96 -.8** -0.63-9.7** -1.50-8.85** -.0-7.59** -0.63 1 LER -5.0** -5.** -5.38** -10.5** -10.5** -10.56** Note: ADF: Augmented Dickey-Fuller unit root test; PP: Phillips-Perron unit root test; T: Trend term included in the unit root test; C: Constant term included in the unit root test; N: No trend and constant terms are included in the unit root test; : The first differenced variables; **: Variables stationary at 5%; *: Variables stationary at 10%; Mckinnon critical values for rejection of hypothesis of a unit root for PP and ADF tests: 1% = -3.8, 5% = -.88, 10% = -.57 (with constant only); 1% = -.03, 5% = -3., 10% = -3.1 (with constant and trend included) 1% = -.58, 5% = -1.9, 10% = -1.61 (no trend and constant term). The results were obtained using lags. The lag for VAR is determined by using several criteria. The ultimate first step entails choosing a set of lag lengths for the VARs that produce mathematical stability, that is, the companion matrix has roots less than unity in absolute value, (or equal, under cointegration, to plus 1), the Akaike information criterion, misspecification tests such as autocorrelation, heteroscedasticity, no ARCH and normality. These diagnostic tests are also supplemented by the tests of graphic analysis which includes recursive graphics and stability tests to evaluate system (parameter) stability. The graphical analysis involves the actual and fitted values (to describe the fitted and actual values) of the equations over time, including the 1 step forecast, cross-plot of actual and fitted (to describe the cross plot of actual and fitted values) and residual density (to show histogram of the residual of the equations); while the recursive graphics analysis involves residual sums of squares, 1 step residuals with 0± σ (this helps to reveal any model deficiencies by showing v_t and twice equation standard error at each t on other side of zero), loglikelihood/t at each t, break-point (N down) Chow tests (to test the stability of the equation). Therefore, taking the information above into consideration, we employed lags. Also, we included (impulse) dummy variables on the basis of economic rationale which 9

includes correction for the outliers and most especially to reflect the deregulation of the Nigerian economy, through the introduction of the structural adjustment programme (SAP) exchange rate, interest rates, were effectively liberalised in 1986 16. Perhaps, the addition of further dummy variables could have eliminated the normality problem but the robustness of Johansen procedure to many dummy variables is not known Cheung and Lai (1993) and Gonzalo (199). The results indicate that our VARs are mathematically stable. The roots of the companion matrix always less than 1 in absolute value, while the diagnostic tests such as the autocorrection, heteroscedasticity, and ARCH tests indicate that there is no autocorrection, heteroscedasticity and ARCH, as presented in Table : Variables Table : Diagnostic Tests Results AR AR 1-5 F(5, 98) Normality Normality χ ( ) ARCH ARCH F(, 95) LPM 0.7955 [0.555] 5.89 [0.071] 0.7715 [0.891] LPD 1.0705 [0.3815] 11.859 [0.007] ** 0.70307 [0.5918] LCP 0.79918 [0.559] 17.19 [0.000] ** 0.7081 [0.5919] LER 0.6391 [0.6819] 0.983 [0.7795] 1.3503 [0.157] From Table, we observed that the residuals are not normally distributed with the exception of LPM and LER. In sum, given the graphic analysis, actual and fitted values, and the cross plot of actual and fitted as depicted in panel A and B and also the recursive analysis (one step residuals) as depicted in Panel C of Figure 1, though the data performed very well as revealed by our results (the results are good for all the variables where the series are all within the 5% band). Thus, not all our tests as presented in Figure 1 above indicate perfect results, (especially the normality of the residuals which are mainly due to the presence of excess kurtosis), but the key mathematical and statistical results are fulfilled by our VARs, therefore, we argue that our VARs are acceptable channel to investigate the presence of long run relationships. 16 Though the adjustment is still on course, recent International Monetary Fund (IMF, 001) reports on Nigeria observed that the policies are now gradually being relaxed. 10

Figure 1: Graphic Analysis Panel A: Actual and Fitted Values LPM LPD LCP LER Fitted LPM Fitted LPD Fitted LCP Fitted LER 5.3 5.5..5 3.1 3.5 3.5 1 3.9 3 1970 1975 1980 1985 1990 1995 000 1970 1975 1980 1985 1990 1995 000 1970 1975 1980 1985 1990 1995 000 1970 1975 1980 1985 1990 1995 000 Panel B: Cross Plot of Actual and Fitted LPM LPD LCP LER 5.5 LPM x Fitted 5 LPD x Fitted.75 LCP x Fitted.3 LER x Fitted 5.5.75.5..5.5 3 3.75.1 3.5 3.75 3.5 3.9 3.5 1 3 3. 3.6 3.8...6.8 5 5..5 1 1.5.5 3 3.5.5 5 5.5 3 3. 3. 3.6 3.8...6.8 3.8 3.85 3.9 3.95.05.1.15..5.3 Panel C: The Recursive Analysis LPM LPD LCP LER r LPM.15 r LPD r LCP.075 r LER.1.1.075.05.05.05.05.05.05 0 0 0 0.05 -.05 -.05.05 -.05.075 -.1 -.1 -.05 1985 1990 1995 000 1985 1990 1995 000 1985 1990 1995 000 1985 1990 1995 000 Table 3 reports both the trace and maximum eigenvalue statistics for co-integration tests between import unit values, domestic PPI, Nigeria s trading partners production costs and exchange rate. It is difficult to assume that the domestic Nigeria output or prices play a role in the determination of the production costs or the exchange rate but the opposite deterministic relationship is plausible 17. 17 In the examination of pass-through for larger open economies such as the US, Japan, Germany, it may be plausible that the domestic exchange rate could affect the foreign cost structure. However, given the fact 11

Table 3: Multivariate Co-integration Test Results: Aggregate and SITC Sections Aggregate: LPM, LPD, LCP and LER Null Hypothesis λ -max Statistic Crit. Val.95% Trace Statistic Crit. Val.95% r = 0 r = 1 r = r = 3 38.9** 18.7 9. 5.57 31.50 5.50 19.00 1.30 7.07** 33.15 1.88 5.57 63.00.0 5.30 1.30 Note: ** (*) indicates hypothesis acceptance at 1% (5%) confidence level. An unrestricted constant, a restricted trend and three seasonal dummies were included in the co-integration space. According to results in table 3, evidence is found for one co-integrating relationship. From the recursively obtained eigenvalues, the estimates of the vectors for aggregate pass-through is constant. Table : Estimate of Pass-Through LPM tot = 1.00 LCP + 1.00 LER + 0 LPD 0.0006t χ 6 = 38.11 D denotes dummy variable while t denotes trend ( ) [ 0.00] In table, we presented the estimated co-integrating vectors. The tests of the restrictions on the co-integration vector was conducted jointly with a test of the hypothesis that LPD, LCP and LER are weakly exogenous 18. The test is conducted by imposing row restrictions on α to yield a new restricted model. Also, we test for cross coefficient restrictions to ascertain if the coefficient on Nigeria s exporters production costs and the exchange rate are equal. The rejection of exclusion restriction implies that for aggregate import unit values, the hypothesis of full pass-through from Nigeria s trading partners production costs and exchange rate changes cannot be accepted. The χ statistics refer to the exclusion restrictions on domestic prices and weak exogeneity, where p- value is in bracket. Furthermore, the dynamics to the long run equilibria was estimated (the result is presented in Table 5). This is of interest because it indicates the behaviour of the changes that Nigeria is a small open economy and the small share of Nigeria s trade in the trading partners trade, such hypothesis is not appropriate in this study. 18 The tests for weak exogeneity was conducted to ensure that it is valid to condition on the LPD, LCP and LER variables and use single equation estimation of the dynamic relationship. Thus, the test for weak exogeneity for LPD, LCP, and LER requires restrictions to be placed on the weighting matrix, the standardized α eigenvectors. 1

in import unit values over time, providing addition information on pass-through. The variables included were four lags of LPM it, LCPit, LERt and LPDit. Table 5: The Results FIML Estimates of the Adjustment to the Long Run Equilibrium Relationships 19 Aggregate Pass-Through Equation for DLPM Variable Coefficient Std.Error t-value t-prob DLPM_ 0.590 0.083159 3.115 0.003 DLPD_3 0.6788 0.7101.387 0.0186 DLCP_ 0.6906 0.1336.019 0.060 DLER_ 0.86165 0.08809 9.76 0.0000 ECM_1-0.15059 0.0371 -.337 0.0000 Constant -0.0331 0.011003 -.10 0.036 Seasonal 0.06068 0.01358 1.97 0.0568 Seasonal_1 0.05167 0.01516 3.59 0.000 Seasonal_ 0.037 0.01366.606 0.010 log lik =1576.009 log Ω = 5. 66 Ω = 7.361e 01 T = 13 Single Equations Diagnostic Tests: Error auto-correlation: F(5, 109) = 0.66838 [0.68]; Normality: χ ( ) = 15.507 [0.000] ** ARCH: F(, 106) =.0786 [0.5611]; Heteroscedasticity: F(10, 103) = 0.8968 [0.893] Systems Tests Error auto-correlation: F(80, 361) = 1.389 [0.0987]; Normality: χ ( 8) = 38.19 [0.0000] ** ARCH: F(100, 68) = 0.9016 [0.7379]; Heteroscedasticity: F(00, 777) = 0.871 [0.99] The equilibrium correction term generated from the co-integration equations was included as an additional channel through which the speed of pass-through can be estimated (denoted as ECM ). Parsimony was achieved by removing the insignificant t regressors and testing the validity of the reduction by an F - test. The parsimonious vector error correction (VECM) was subjected to a number of diagnostic checks, including stability, within equation residual serial correction, heteroscedasticity, and normality tests. Our results revealed that full pass-through from the exchange rate and trading partners cost of production could not be accepted. The long run relationship shows that a 1 percent change in the exchange rate and the exporters foreign cost of production leads to 0.86 percent and 0.6 percent increase in import prices respectively. The results suggest 13

that supplier pass on additional costs by selling their products at higher prices, all things being equal. Also, the speed of adjustment -0.15 implies that following shocks, the system takes a short period to adjust towards equilibrium. 6.1 Conclusion In this paper we examine the degree of pass-through from producers costs and the exchange rate to the prices of Nigeria imports from her major trading partners using quarterly aggregate data. We used the mark-up model and our results revealed that full pass-through from the exchange rate and the major trading partners producer costs could not be accepted for the aggregate import unit values. Our findings accord much more closely to the incomplete pass-through hypothesis. Also, to place our results in context, a comparison with the findings from small open economy would be in order. Studies mentioned above that focused on small open economy include Lattimore (1988), Moreno (1989), Phillips (1991) and Menon (1995) for Australia, and Menon and Athukorala (199) for Korea. Our results of incomplete pass-through for both aggregate and sectors under consideration compare favourably with evidence available from small open economies most especially for Australia, Sweden and Korea. References Athukorala, P. (1991) Exchange Rate Pass-Through: The case of Korea Exports of Manufactured. Economics Letters, 35, pp 79-8 Athukorala, P. and Menon, J. (1995) Exchange Rate and Strategic Pricing in Swedish Machinery Exports. Oxford Bulletin and Statistics, 57 Bhagwati, J. (1988) The pass-through puzzle: the missing prince from Hamlet, Discussion paper, University of Columbia, December Central Bank of Nigeria (CBN), Tinubu, Lagos, Nigeria; Economic and Financial Review (various issues) Statistical Bulletin (various issues) Dornbusch, R. (1987) Exchange Rate and Prices. American Economic Review, 77, pp 93-106. 19 Common statistics such as R, R etc are not reported by this type of model estimation. 1

Enders, W. (1995) Applied Econometric Time Series, Wiley and Sons Inc. Engle, R. F. and Granger, C. W. J. (1987) Co-integration and Error Correction: Representation, Estimation and Testing. Econometrica, 55 (March), pp 51 76. ---------, eds., (1991) Long Run Economic Relationships, Readings in Co-integration. Oxford, New York, Oxford University Press. Feenstra, R. C., Gagnon, J. E. and Knetter, M. M. (1996) Market share and exchange rate pass-through in world of automobile trade, Journal of International Economics, 0, pp 187 07. Federal Office of Statistics (FOS), Ikoyi, Lagos, Nigeria; Annual Abstract of Statistics (various issues) Review of Statistics (various issues); Monthly Digest of Statistics (various issues) Froot, K. A. and Klemperer, P. D. (1989) Exchange rate pass-through when market share matters, American Economic Review, 79,, 637 65. Goldberg, P. K. and Knetter, M. M. (1997) Goods Prices and Exchange Rate: What Have We Learned? Journal of Economic Literature, 35 (3), pp 13 17. Isard, P. (1977) How Far Can we Push the Law of One Price? American Economic Review, 67 (5), pp 9 98. International Monetary Fund; Direction of Trade Statistics (Quarterly); International Financial Statistics (Monthly); International Financial Statistics Yearbook (Annual); IMF CR Rom Johansen, S. (1988) Statistical Analysis of Cointegration Vectors. Journal of Economic Dynamics and Control, 1, pp 31 5. Johansen, S. and Juselius (1990) The Full Information Maximum Likelihood procedure for inference on Co-integration with applications to the demand for money, Oxford Bulletin of Economics and Statistics, Vol. 5, pp 169 10. Kenny, G. and Mcgettigan, D. (1996) Exchange Rate Pass-Through and Irish Import Prices. Economic Analysis, Research and Publication Department, Central Bank of Ireland. Kikuchi, A. and Sumner, M. (00) Exchange Rate Pass-Through in Japanese Export Pricing. Applied Economics, Vol. 3, No 3, P 79 8. Kreinin, M. E. (1977) The effect of Exchange Rate changes on the Prices and volume Of Foreign Trade. International Monetary Fund Staff Papers, 7, pp 07 9. 15

Krugman, P. (1987) Pricing to Market when the Exchange Rate Changes, in Real- Financial Linkages among Open Economies, eds.: Sven, W. and Richardson, J. D. MIT Press, pp 9 70. Menon, J. (199) Exchange Rates and Prices of Australia Manufactured Exports. Weltwirtschaftliches Archiv, 18 (). Menon, J. (1993a) Exchange Rate Pass-Through: Australian Imports of Motor Vehicles. International Economic Journal, 7, pp 93 109. Menon, J. (1993b) Exchange Rates, Import Prices and the Macroeconomy. Economic Papers, 1, pp 37 8. Menon, J. (199) The Theory of Exchange Rates and Traded Goods Prices in the shortrun. Economia Internatzionale, XLVII, pp 55 68. Menon, J. (1995) Exchange Rate and Import prices for a Small Open Economy. Applied Economics, Vol. 7, No. 3, pp 97 301. Moreno, R. (1989) Exchange Rates and Trade Adjustment in Taiwan and Korea. Federal Reserve Bank of San Francisco Economic Review,, pp 30 8. Organisation for Economic Co-operation and Development (OECD); Indicators of Industrial Activities; Economic Surveys: France, Germany, Italy, Japan, Netherlands, United Kingdom, United States Economic Outlook; Financial Statistics; Statistical Bulletins; Statistical Bulletins Agriculture and Food Statistics; International trade by Commodities Statistics Database: Average earnings Index by industry published in the Employment Gazette and Labour market trends, (NSO) Phillips, R. W. (1988) The Pass-Through of Exchange Rate changes to Prices of Imported Manufactures. Discussion Paper No. 197, Centre for economic Policy Research, Australian National University, Canberra. Taylor, M. P. and Sarno, L. (1998) The behaviour of real exchange rate during the post Bretton Woods period, Journal of international Economics, 6,, 81 31. United Nations (199) Commodity Indexes for the Standard International Trade Classification, Revision 3, United Nations Statistical Papers Series M, No. 38/Rev, New York. Venables, A. J. (1990) Microeconomic Implications of Exchange Rate changes. Oxford Review of Economic Policy, 6 (3), pp 18 7. World Bank, Washington D.C.; African Development Indicators (various issue); African 16

Economic and Financial Data (various issues) 17