Real exchange rate volatility can impact a country's productivity growth, especially in less financially developed countries. For these countries, exchange rate volatility tends to reduce growth, while financially advanced countries are not significantly affected. The study analyzed data from 83 countries between 1960-2000 and found that real exchange rate uncertainty worsens the negative effects of credit market constraints on investment. This contrasts with previous research that often downplays the impact of exchange rate volatility on economic activity.