Approaching a problem of the long-run real equilibrium exchange rate of Polish zloty while entering the ERM-2 and Euro zone

Taking into account a large number of types of nominal and real exchange rates, while estimating the real equilibrium exchange rate, one should always remember that there is no a single, universal equilibrium exchange rate. A point value or a path of that exchange rate depends on the adopted definitions and assumptions as well as on the method and purpose of the analysis. However, a value added of each estimation of the equilibrium exchange rate is an answer, whether the economic policy causes upset or stabilisation of the economy. Moreover, in the period of discussion on the exchange rate of accession to ERM-2, showing an interval of the exchange rate where all values of the exchange rate ensure at least suboptimal behaviour of the economy may help to make a decision on the date of accession to ERM-2 that will minimise costs of retention of the exchange rate within a definite currency band. For Poland, estimated by the NATREX method the long-run real equilibrium exchange rate ensures the internal equilibrium with annual growth rates of GDP amounting to 4.1%, comprised of growth of consumption by 4% p.a., investment by 8.7%, volume of exports by 8.5% and volume of imports by 8.1% p.a. Estimating on the ground of real exchange rates an approximate value of nominal exchange rates, one can state that the long-term equilibrium in the economy is ensured with the exchange rate of 3.80-3.90 zlotys for 1 euro. The current exchange rate will probably approach the equilibrium exchange rate at the turn of 2010 and 2011, and it will remain near that level over 5-6 quarters. This means that in that period cost of retention of the PLN exchange rate within a narrow band of fluctuations is relatively the least. The next period where the current exchange rate should approach the optimal exchange rate is 2014. Then, also in the medium term, the exchange rate of zloty should be comprised within the interval of 3.80-3.90 (assuming the stable exchange rate of USD/EUR=1.40)