The paper examines the historical properties of business cycles in ten countries over the last century, focusing on real quantities, price levels, and money stocks. Despite variations in the magnitude of output fluctuations across countries and periods, the relationships among real quantities have been remarkably consistent. Inflation rates have become more persistent after World War II, and price level fluctuations have been procyclical before the war but countercyclical afterward. Money fluctuations have less correlation with output in the postwar period but are no more persistent. The study also finds that consumption expenditures are procyclical and have similar variability to output, while investment is more variable and strongly procyclical. Government spending is more variable than output but exhibits countercyclical behavior. Net exports are generally countercyclical. The data supports the idea that business cycles involve not just fluctuations in aggregate output but also common patterns of correlation between different economic variables. The findings extend previous research on U.S. business cycles to a broader set of countries and time periods, providing insights into the dynamics of international trade and the relationships among business cycles in different countries.The paper examines the historical properties of business cycles in ten countries over the last century, focusing on real quantities, price levels, and money stocks. Despite variations in the magnitude of output fluctuations across countries and periods, the relationships among real quantities have been remarkably consistent. Inflation rates have become more persistent after World War II, and price level fluctuations have been procyclical before the war but countercyclical afterward. Money fluctuations have less correlation with output in the postwar period but are no more persistent. The study also finds that consumption expenditures are procyclical and have similar variability to output, while investment is more variable and strongly procyclical. Government spending is more variable than output but exhibits countercyclical behavior. Net exports are generally countercyclical. The data supports the idea that business cycles involve not just fluctuations in aggregate output but also common patterns of correlation between different economic variables. The findings extend previous research on U.S. business cycles to a broader set of countries and time periods, providing insights into the dynamics of international trade and the relationships among business cycles in different countries.