As an AI language model, I do not have access to real-time data. The rates of unemployment and their fluctuations are subject to change based on various factors like economic conditions and government policies. However, to provide some general information, here are ten countries that have experienced a significant decrease in unemployment rates based on available data as of recent years:
1. United States
4. United Kingdom
7. South Korea
Please note that the rankings and specific data may vary depending on the source and the time frame being considered. I encourage you to refer to reputable sources like the International Labour Organization (ILO), World Bank, or national statistical offices for the most accurate and up-to-date information on unemployment rates.