Nominalni i realni (efektivni) devizni kursevi značajno osciliraju, i to uvek u tandemu, što ima savršenog smisla ako se devizni kurs posmatra preko cena imovine i lepljivih robnih cena.
Na godišnjem nivou, devizni kursevi posmatrani preko cena imovine oscilirali su u značajnoj meri. Slično je i sa realnim deviznim kursem, zbog lepljivih robnih cena. Prilagođavanje ravnoteži teče usporeno jer se ono daleko sporije postiže na robnom tržištu (preko uticaja agregatne tražnje na autput). Prilagođavanje na finansijskom tržištu podrazumevaju razvijeno finansijsko tržište što nije slučaj u Srbiji.
Sa stabilizovanjem inflacije, posebno poslednjih nekoliko (6) kvartala, kretanje nominalnog i realnog deviznog kursa bilo je gotovo istovetno (od Q4 2012. godine vrednosti indeksa realnog deviznog kursa su približno jednake).
Podaci na mesečnom nivou pokazuju mnogo veću varijabilnost deviznog kursa što sugeriše da su cene „lepljive“ u kratkom roku. Dakle, reč je o kratkoročnoj rigidnosti cena naspram dugoročne fleksibilnosti cena. Ta rigidnost cena više je izražena kod razvijenih ekonomija sa umerenom inflacijom nego kod manje razvijenih ekonomija, kao što je Srbija.
U kratkom roku cene zavise od ponude i potražnje, kao na primer kod poljoprivrednih proizvoda, međutim postoje i brojne cene koje su unete u dugoročne ugovore (zarade, trgovinski ugovori…). Niske zarade, slabiji inflatorni pritisci i visok procenat regulisanih cena u srpskoj privredi narušava pravu sliku, uz svakako obimne intervencije NBS na deviznom tržištu, kako bi ublažili prekomerne oscilacije kratkoročnog deviznog kursa (pritisak na cene, ali i na bilanse realnog i javnog sketora zbog neusklađenosti njihovih potraživanja i obaveza).
Unutar modela međunarodne makroekonomije postoji veoma čvrsta veza između nominalnog i realnog deviznog kursa, što govori da model uključuje „lepljive“ cene u ekonomiji. Najbolji primer predstavjla sjajni Dornbušov model premašaja (Overshooting model) – oscilacije deviznih kurseva uslovljene su različitom brzinom prilagođavanja cena na finansijskom (brže) nego na robnom (sporije) tržištu. Uključivanjem u analizu forvard finansijskih tržišta, uz zadržavanje realnog pogleda na ponašanje cena na robnom tržištu održava se značaj kejnzovog stanovišta. Sa druge strane, postojanje „lepljivih“ cena teško je pronaći kod neoklasičnih modela.
Napomena: promene u deviznom kursu (y0y), podaci NBS
Nominal and real (effective) exchange rates exhibit significant fluctuations, and they almost always move in tandem. This outcome is fully consistent when exchange rates are viewed through the lens of asset prices and sticky goods prices.
On an annual basis, exchange rates observed through asset prices have fluctuated considerably. A similar pattern is observed for the real exchange rate due to sticky goods prices. Adjustment toward equilibrium is slow because it is achieved much more gradually in the goods market (through the impact of aggregate demand on output). Adjustment in the financial market, on the other hand, requires a well-developed financial system, which is not the case in Serbia.
With the stabilization of inflation, particularly over the last six quarters, movements in the nominal and real exchange rates have been almost identical. Since Q4 2012, the index values of the real exchange rate have been approximately equal.
Monthly data reveal much higher exchange rate variability, suggesting that prices are “sticky” in the short run. This reflects short-term price rigidity versus long-term price flexibility. Price rigidity is more pronounced in developed economies with moderate inflation than in less developed economies such as Serbia. In the short run, prices depend on supply and demand conditions, as in the case of agricultural products; however, many prices are determined by long-term contracts (wages, trade contracts, etc.). Low wages, weak inflationary pressures, and a high share of regulated prices in the Serbian economy distort the true picture, along with extensive interventions by the National Bank of Serbia in the foreign exchange market aimed at smoothing excessive short-term exchange rate fluctuations (which otherwise exert pressure on prices and on the balance sheets of both the real and public sectors due to mismatches between assets and liabilities).
Within international macroeconomic models, there is a very strong link between nominal and real exchange rates, indicating that such models incorporate price stickiness. The best-known example is Dornbusch’s overshooting model, in which exchange rate fluctuations arise from different speeds of price adjustment in financial markets (faster) compared to goods markets (slower). By incorporating forward financial markets while maintaining a realistic view of price behavior in goods markets, the Keynesian perspective remains relevant. In contrast, price stickiness is difficult to identify in neoclassical models.
Note: Exchange rate changes (year-on-year), National Bank of Serbia data.