Indonesia's Currency Weakness Defies Standard Macroeconomic Explanations

Indonesia's economy presents a puzzling paradox: robust growth, low inflation, and ample foreign reserves coexist with a weakening rupiah and stock market. Standard macroeconomic theories, which predict currency appreciation with such indicators, fall short. The author, Adiwarman A. Karim, an Islamic economics observer, attributes this to unmet assumptions in Indonesia's economic model, particularly regarding economic openness and the distinction between currency 'voice' and 'noise'.

Karim highlights Indonesia's limited economic openness, citing measures like trade intensity and global economic openness indices, which show the country lagging. He points to three main channels of openness: exports-imports, foreign loans, and foreign investment. A key issue identified is the 'currency mismatch' – a situation where a country's loans are predominantly in foreign currency, but its revenue is in the local currency. Indonesia fits this description, meaning fiscal and monetary expansions in rupiah directly impact the exchange rate. This mismatch necessitates sterilization policies to absorb global shocks and maintain the rupiah's stability, creating a delicate balance between central bank independence and fiscal growth policies.

The analysis also delves into distinguishing between currency 'voice' (fundamental economic factors) and 'noise' (speculative or short-term fluctuations). Furthermore, it touches upon segmenting the economy based on marginal propensity to consume, macro multiplier effects, and varying money circulation velocities. Ultimately, Karim suggests that the persistent currency mismatch, coupled with external dependencies, is the primary driver behind the rupiah's depreciation, defying conventional economic expectations.