Foreign Versus Domestic Factors as Souces of Macroeconomic Fluctuations in Hong Kong

This paper uses a semi-structural vector autoregression approach to estimate the relative importance of domestic and foreign shocks as sources of macroeconomic fluctuations in Hong Kong since the adoption of the currency board. We find that external factors are clearly dominant in the medium to long run. In view of the highly open nature of the Hong Kong economy and the linkages implied by the currency board arrangement, it is perhaps not unexpected. However, that these factors should account for fifty percent or more of unexpected fluctuations in real GDP and the GDP deflator at shorter horizons of one to two years is more surprising, and it is large in comparisons with other highly open small economies. Even if external shocks are dominant sources of macroeconomic fluctuations, there remain significant short-term influences of domestic variables. For example, in the historical decomposition of the evolution of output growth and inflation we discovered a significant role for domestic factors in the recent recession. Their impact resembles very much those that would be generated by a conventional aggregate supply contraction. A challenge for future research is to identity empirically the exact sources of the domestic shocks.