Export Market Integration in the European Union^* by ** Salvador Gil-Pareja *** Simón Sosvilla-Rivero DOCUMENTO DE TRABAJO 2002-07

March 2002

The authors are very grateful to Oscar Bajo-Rubio for very helpful comments and suggestions. Salvador Gil-Pareja acknowledges financial support from the University of Valencia, through Project UV01-03.

Universidad de Valencia

FEDEA y Universidad Complutense de Madrid

Abstract

This paper examines the degree of export-price dispersion among European Union countries and its evolution in the recent past (1988-1999). The paper also explores the likely impact of the European Monetary Union on export-price convergence by looking at the past experience of European countries that participated in the exchange rate stability zone. The results indicate that exportprice dispersion across European Union countries was usually lower than across OECD countries. Moreover, although there is little evidence of convergence, it is stronger across European Union countries. Finally, the results cast doubts on the hypothesis that the monetary union by itself will increase price convergence.

JEL classification numbers: F15, F33, O52.

KEY WORDS: Export market integration, European Union, Single currency.

1. Introduction

The integration of national economies in Europe is the focus of an intense debate in policy making circles [see, e. g., European Commission (1999) and European Central Bank (2001)]. One expected effect of the European market integration is the convergence of prices. In particular, the elimination of barriers to trade by the single market programme and the adoption of the single currency should reduce the potential for price discrimination across European Union (EU) markets. Documenting trends in price convergence over time is interesting in itself. But, additionally, it provides an indicator of the evolution in product market integration.

There are few empirical studies on price convergence in Europe and they do not pay attention to the behaviour of exporters in the European markets. This paper attempts to fill a part of that gap by investigating the degree of export-price dispersion among EU Member States and its evolution in the recent past. The paper also explores the likely impact of the European Monetary Union (EMU) on export-price convergence, by looking at the past experience of the countries whose currencies participated in the core of the European Monetary System (EMS).

The approach used here deviates from the traditional convergence literature in that it uses highly disaggregated data. Most work with disaggregated products compares prices of goods sold in different locations (which include different amounts of value added that are non-tradable, such as distribution and retail services) and/or produced in different countries (which raises questions about the homogeneity of the goods on the one hand, and about the differences in terms of the costs of production on the other). Moreover, the sample size of most studies is limited in the extent of cross-section or time series variation. Goldberg and Verboven (2001) focuses on price convergence in the European automobile market. Haskel and Wolf (2001) examines absolute prices for goods sold by IKEA, a Swedish furniture retailer. Crucini, Telmer and Zachariadis (2000) use actual prices for a large sample of items in European cities, but only for 1985. In a similar fashion, De Serres, Hoeller and De la Maisonneuve (2001), analyse price dispersion in Europe using data at one point in time only (1998). Finally, Rogers (2001) and Rogers, Hufbauer and Wade (2001) investigates price level convergence and inflation in Europe using data from 1990, 1995, and 1999.

¹ To our knowledge, only Knetter and Slaughter (1999) consider prices charged by exporters to various destination markets. In particular, these authors study export-price dispersion across OECD markets and over time from two source countries: Germany and the United States.

Our approach offers two main advantages. Firstly, the use of export prices at the border of the exporting country implies that no assumptions about transportation costs or the competitiveness of distribution networks in the buying countries are required, in contrast to the approach that compares prices of goods in different countries. The only critical assumption is identical products. But, this assumption seems more reasonable in our case than when the comparison is based on goods produced in different countries. Secondly, we use a wide sample that allows us to examine export prices across groups of destination markets, products and source countries. By investigating price dispersion and price convergence in multiple dimensions, we hope to offer a comprehensive analysis on these issues.

The paper is organised as follows. Section 2 discusses the approach used to study price dispersion and price convergence over time, which is based on export prices at a common location. Section 3 presents the data. Section 4 offers the empirical findings. Finally, section 5 concludes the paper.

2. The law of one price and export market integration

One of the cornerstones in international economics is the proposition known as the law of one price. This proposition states that in a fully integrated market identical products should sell at the same price net of relocation costs when expressed in a common currency. The intuition is that international arbitrage should work until prices net of relocation costs are aligned. In particular, if for some reason, the price differential between two markets exceeds the costs of relocating the product from the market in which its price is lower to the market where it sells at a premium, the product would be shipped from the low-price location to the high-price location and the resulting changes in supply would eliminate the observed price difference.

Most of the empirical literature on the law of one price examines its relative version, which is compatible with the existence of a stable price differential across markets. As pointed out by Goldberg and Knetter (1997) and Knetter (1997), that fact is a consequence of data limitations rather than research interest. This paper focuses on the absolute version of the law of one price. Obviously, the existence of relocation costs precludes price equalisation when comparing prices at different countries. However, the same arbitrage forces that imply products in different locations differ in price by no more than relocation costs also imply that products at the same geographical point carry identical prices. This is because relocation costs are zero if products are at the same location. This notion can be applied to f.o.b. export prices. The export currency price for an identical product at the border of the exporter country should be the same across buyers. Thus, price discrimination by exporters across destinations at a common location is inconsistent with the law of one price. At this point, it is important to note that there are limits to the use of price dispersion as an accurate indicator of integration. Even within fully integrated markets export prices may vary to a certain extent due to changes in income or to exchange rate fluctuations. In addition, data limitations may be masking product differentiation across markets. Therefore, the analysis of export-price dispersion can only provide a rough indication about the integration of export markets.

² In this paper we use unit values, so destination-specific quality differences in the product may give rise to differences in unit values, even though prices for identical varieties are the same. However, it is important to note that the scope for quality differences is likely to be minimal for most of the products studied here.

3. Data

The data used in this study are based on the annual f.o.b. value and quantity of exports to selected destination countries for a large number of eightdigit products from seven source countries: Belgium-Luxembourg, France, Germany, Italy, the Netherlands, Spain, and the United Kingdom. The sample period is 1988-1999. For each source country, given the destination-specific values and quantities of shipments, destination-specific unit values are constructed over the sample period to be used as a measure of export prices. The data are taken from Eurostat’s statistics on external trade (Comext database).³

For each source country, the product selection was done in two stages. First, the main exported products were selected. Second, some products where excluded due to the high concentration of their exports (in less than eight destinations), the existence of statistical confidentiality, the unusable quantity figures, or the relatively high heterogeneity in the product category.

The destination markets selected are those OECD countries which are the main customers for each source country-product pair. The selection of large export destinations was made with the aim of improving the accuracy of the unit values as a measure of average prices. Large destinations are preferred in constructing unit values, since erratic variation in exports to small destinations could increase the amount of noise in the unit value series.

Before proceeding to analyse the empirical results, it is worth emphasising three features of the sample. First, the sample provides variation in terms of the type of products. Second, most products are exported from more than one of the source countries in the sample. It is useful to compare the empirical evidence across source countries. Third, for each source country there is a set of common destinations across products. In particular, for each export source, the common set of destination markets includes the remaining six Member States from the list of source countries. It allows us to study price dispersion and price convergence among an important common set of Member States, as well as to analyse the influence of exchange rates on these issues.

³ In this study, the products are classified on the basis of eight-digit subheadings of the Combined Nomenclature. Since January 1, 1988 the Combined Nomenclature is the tariff and statistical codification system of the European Union countries, replacing the old nomenclatures Nimexe (statistical) and CCT (Common Customs Tariff). The successive versions of this nomenclature comprise about 10,000 eight-digit subheadings. In general, the change in trade classification that took place in 1988 prevents the use of earlier data.

4. Empirical results

As set out before, we study the dispersion of export prices across markets and over time using export unit values from seven source countries: Belgium-Luxembourg, France, Germany, Italy, the Netherlands, Spain, and the United Kingdom. As a measure of export-price dispersion we use the coefficient of price variation. For each source country-product pair, the coefficient of variation is calculated for each year across several sets of destination markets.⁴ Then, the average coefficients of variation over the sample period are calculated in order to investigate the extent of price dispersion. For the purpose of assessing price convergence, the time series of coefficients of variation for each source country-product pair (CV_t) are regressed on a constant (α) and a linear time trend (TIME):

\[C V _ {t} = \alpha + \beta T I M E + u _ {t}\tag{1}\]

where is the error term. If price dispersion were declining steadily, we would expect the regression to yield a negative coefficient for the linear time trend.

Tables 1-7 present the results for the products considered in each one of the seven source countries. In particular, each table reports, for each product, the average coefficient of variation over the sample period, and the estimated linear trend in the coefficients of variation for four different samples. The first sample uses export prices to OECD countries and we have referred to it in the tables as “OECD”. In this case, it is important to note that the set of destinations is not fixed and, therefore, the variation in the results across products may partly reflect variation in the markets in the sample. Despite that caveat, this sample is useful because it provides a benchmark that allows us to evaluate the evidence on export-price dispersion across EU Member States. The second sample uses export prices to the remaining six EU Member States from the list of source countries. We have called it as . In this case, for each source country, the set of destination markets is common for all products in the sample. For example, for Belgian-Luxembourg exports (Table 1) the common set of destination markets is the group of countries consisting of France, Germany, Italy, the Netherlands, Spain, and the United Kingdom. The third sample (“EU6 group A”) examines price dispersion and price convergence for those EU6 countries whose currencies have continuously participated in the exchange-rate mechanism (ERM) of the EMS from its inception (Belgium-Luxembourg, France, Germany, and the Netherlands). These continuous participants in the ERM have maintained broadly stable bilateral exchange rates among themselves and, in particular, against the German mark over the sample period. Finally, the fourth sample (“EU6 group B”) includes those EU6 countries whose currencies have fluctuated in value to a great extent relative to the German mark (Italy, Spain, and the United Kingdom).

CV_t=σ_t/µ_t.

⁴ The coefficient of variation (CV) equals the standard deviation of the export prices across countries within a given period (σ_t) divided by the mean of export prices across countries for that period (µ_t):

Firstly, we focus on the similarity between export prices and their convergence over time in EU6. The analysis is based on a comparison of the empirical evidence in both EU6 and OECD countries. The average coefficient of variation over the 1988-1999 period is higher among OECD countries than among EU6 countries in 111 of the 134 source country-product pairs. The analysis of the results by source countries reveals that this is the case in the following percentages of products: Belgium-Luxembourg, 53%; France, 100%; Germany, 81%; Italy, 87%, Netherlands, 100%; Spain, 78%; and United Kingdom, 87%. In relation to the extent of export-price dispersion, the coefficients of variation are below 0.15 (0.10) in 54% (22%) of the source country-product pairs in the OECD sample. These percentages raise to 78% (48%) for the sample of European Union countries, indicating a relatively high level of integration of markets. In summary, the results indicate that exportprice dispersion is usually lower among EU6 countries than among OECD countries, and that the degree of price similarity is high in the first group, although there is room for further improvement.

As noted earlier, a feature of the sample is that most products are exported from at least two source countries. This fact allows us to identify those products for which the evidence of a high or a low degree of export-price dispersion in the EU6 sample is pervasive across the source countries. There are several products (malt beer, fertilizers, polypropilene, flat rolled products of iron, aluminum alloys, and ball bearings) for which the average coefficient of variation is higher than 0.10 in nearly all of the source country-product pairs. For these products, that result is found in 22 of the 24 pairs. In contrast, the measure of export price-dispersion is below 0.10 for all or most of the pairs in common wheat, polyvinyl chloride, copper wire, and washing machines (in all pairs considered in each case), polyethylene (in six of the eight pairs), car tyres, and truck and bus tyres (in nine of the 13 pairs), and paper for writing (in 10 of the 14 pairs). This also applies to 14 of the 25 pairs of the automobile industry, despite automobiles are among the most differentiated products included in the sample.

⁵ The Italian lira was also part of the ERM from the start, but its participation was suspended from September 1992 to November 1994. The Spanish peseta and the Pound sterling entered the ERM in 1989 and 1990, although the the Pound sterling left the ERM in September 1992. The distinction made between group A and group B countries is consistent with that made in European Commission (1995).

⁶ Of the 25 source country-product pairs for the automobile industry, only one of them shows an average coefficient of variation greater than 0.15.

Turning now to price convergence, we observe that over the 1988-1999 period only 57 of the 134 estimates for the sample of OECD destination markets are negative and only 20 of them are statistically significant at the 10% level. On the other hand, 31 of the 77 positive coefficients are statistically significant.

If we focus on the EU6 sample, there is an increase in the number of negative estimated coefficients, but most of them are again not statistically significant. In particular, 28 of the 74 negative coefficients reach the cited significance level. Of the 60 positive coefficients, it occurs in 25 of them. By source countries, the negative coefficients clearly predominate in exports from Belgium-Luxembourg, France, and Spain, whereas the opposite is true in UK exports. For the remaining source countries, the results are split evenly between both possibilities. Finally, the analysis by products reveals that only one product (fertilizers) shows a significant declining trend in all the pairs considered. Furthermore, the regressions show a tendency for dispersion to fall over time in ten pairs of the tyre industry, and the coefficient is statistically significant in half of the cases. The same result is found in paper for writing. The rest of the products do not show a pervasive trend neither toward lower dispersion nor toward higher dispersion.

Taken together, the evidence we have examined until this point indicates that, in the 1990s, export-price dispersion across OECD countries was usually higher than across EU6 countries, which were already quite closely integrated with each other. Moreover, even though there is little evidence of convergence, it is stronger across EU6 countries than across OECD countries.

Secondly, we examine the impact of exchange rates on export-price dispersion and convergence patterns.⁷ To this end, we analyse whether those EU6 countries with relatively stable exchange rates (group A) witnessed a lower export-price dispersion and a stronger tendency to convergence than countries with relatively volatile exchange rates (group B). By looking at the past experience of group A countries we can also address the possible effect EMU may have on price convergence.

As noted in the introductory material, the single currency should reduce the potential for price discrimination across participating countries. Theoretical support to this notion is provided by Friberg (2001), who shows that a monetary union promote market integration by reducing the option value of segmenting markets. But, to our knowledge, only one study (Nicoletti et al, 2001) has addressed the possible direct effect of monetary integration on the degree of price competition. In this study, using prices over 200 categories of goods and services observed in 1985, 1990, 1993, and 1996, the authors find that countries in the D-mark area have a higher level of price similarity, but they do not find evidence of stronger price convergence than in other EU countries. These results lead them to conclude that is the similarity of economic structures rather than participating in the D-mark area that is behind price similarity, which cast doubts on the hypothesis that the EMU by itself will increase significantly product-market competition and, therefore, price convergence across the euro zone.

Exchange rate fluctuations affect relative export prices between countries in the case of an incomplete exchange rate pass-through. Empirical studies measuring the degree of exchange rate pass-through suggest that European exporters, with the exception of the United Kingdom, often “price to market” by revising export prices to absorb part of the impact of exchange rate changes (see for example the papers by Knetter, 1993; and Gil-Pareja, 2002). On the other hand, a detailed discussion about the role of exchange rates on price convergence can be found in European Commission (1997).

In our case, the average coefficient of variation is lower among group A countries than among group B in 60% of the source country-product pairs. By source countries the percentages of products for which this is the result are the following: Belgium-Luxembourg, 71%; France, 59%; Germany, 75%; Italy, 47%; Netherlands, 60%; Spain 57%; and United Kingdom, 33%. The inclusion of Italy, Spain, and the United Kingdom among the set of source countries in this analysis can be criticised because, although exchange rates have been relatively stable across group A countries, the exchange rate variability between the source country and the destination markets may affect export-price dispersion if the degree of exchange rate pass-through differs across destinations. Therefore, we will focus on exports from Belgium-Luxembourg, France, Germany and the Netherlands. For these source countries, the average coefficient of variation is lower among group A countries in 67% of the pairs. Regarding the degree of export-price dispersion, the coefficient of variation is bellow 0.15 (0.10) in 90% (70%) of the cases for group A, and in 86% (50%) of them for group B.⁸ These results imply that countries in both groups, and especially in group A, are closely integrated with each other.

The relatively higher price similarity across group A countries suggests that a stable exchange rate regime may contribute to price convergence. However, progress toward reducing export-price dispersion has been relatively lower among group A than among group B. In the first group, only 32 of the 86 estimates are negative, and only six of them are statistically significant at the 10% level, whereas in the second, we find significantly lower dispersion over time in 20 of the 54 negative coefficients. On the other hand, the regressions show a significant tendency for dispersion to increase in 15 pairs for group A and in 11 pairs for group B. Thus, the stable exchange rate regime have not contributed to price convergence over the sample period.

⁸ For the full sample of source countries, the coefficient of variation is bellow 0.15 (0.10) in 85% (65%) of the cases for group A, and in 84% (54%) of them for group B.

5. Concluding remarks

This paper has examined the degree of export-price dispersion among European Union Member States and its evolution in the recent past, using OECD countries as a benchmark. In addition, the paper has analysed the likely impact of the European Monetary Union on export-price convergence by looking back the experience of European countries that participated in the exchange rate stability zone.

On the one hand, the results indicate that, between 1988 and 1999, export-price dispersion across the sample of European Union countries was usually lower than across OECD countries, and that, even though there is little evidence of convergence, it is stronger across European Union countries. On the other hand, by looking at the past experience of subsets of European Union countries, we find that price similarity was often higher across those European Union countries where exchange rates have been relatively stable than across countries with relatively volatile exchange rates. However, it seems that the stable rate regime has not contributed to export-price convergence across participating countries over the sample period.

The extrapolation of these results to the impact of the European Monetary Union on price convergence suggests that the monetary integration by itself will not probably be sufficient to reduce the degree of export-price dispersion. However, this extrapolation must be made with caution for several reasons. Firstly, the European Monetary Union is a more credible and irrevocable monetary arrangement than fixed exchange rates. Secondly, the unprecedented monetary turmoil experienced in the ERM during 1992-93 could affected our results, since it led to an impressive increase in volatility in all the currencies analysed in this paper (see Sosvilla-Rivero et al., 1999). Finally, one could argue that by 1988 some price converge could have been already achieved among more stable ERM founding members, in contrast with that registered among new comers (Spain in 1989 and the UK in 1990) or more volatile currencies (Italy, whose currency left the ERM in September 1992 and only rejoined it in November 1996). Nevertheless, although monetary stability could help to price convergence, it does not necessarily lead to a complete price convergence, since the existence of trade costs and pricing to market could explain persistent international price differentials (see, e. g., Obstfield and Rogoff, 2001).

References

1. Crucini, M. J., Telmer, C. I., and Zachariadis, M. (2000): “Dispersion in real exchange rates”, Vanderbilt University, mimeo.
2. De Serres, A., Hoeller, P. and De la Maisonneuve, C. (2001): “ The width of the intra-European economic borders” OECD Economic Department Working Paper No. 304.
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9. Gil-Pareja, S. (2002): “Export price discrimination in Europe and exchange rates”, Review of International Economics 10, 299-312.
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Table 1. Average coefficients of variation and trends in Belgian-Luxembourg export-price dispersion, 1988-1999

Notes: For each Country Group, CV denotes the average coefficient of variation in export unit values across destination markets over the sample period. Each trend is the coefficient estimate of annual export-price dispersion (measured as the coefficient of variation) regressed on a time trend. The regressions include a constant. Country Groups are defined in the text.

Table 2. Average coefficients of variation and trends in French export-price dispersion, 1988-1999

Note: see Table 1.

Table 3. Average coefficients of variation and trends in German export-price dispersion, 1988-1999

Note: see Table 1.

Table 4. Average coefficients of variation and trends in Italian export-price dispersion, 1988-1999

Note: see Table 1.

Table 5. Average coefficients of variation and trends in Dutch export-price dispersion, 1988-1999

Note: see Table 1.

Table 6. Average coefficients of variation and trends in Spanish export-price dispersion, 1988-1999

Note: see Table 1.

Table 7. Average coefficients of variation and trends in UK export-price dispersion, 1988-1999

Note: see Table 1.

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