This study analyses interventions in the Brazilian spot foreign exchange
market from 1999 to 2008 and their effects on the R$/US$ exchange rate,
using an event study approach. It aims to verify if the foreign exchange
interventions have any significant impact on the exchange rate behavior. The
period was divided according to a MS-VAR model and analyzed with different
criterions. The results indicate that prolonged foreign exchange
intervention have a greater effect on the exchange rate behavior, in
comparison to short time intervention episodes. The results also point to
the existence of quickly dissipating effects on the rate behavior. The
creation of a new criterion, based on the analysis of exchange-rate
acceleration, shows that the exchange rate is mainly prone to accelerate on
leaning with the wind purchase intervention episodes.