What facts show the economic success of Germany in the late 19th century?

During the forty years since the unification of Germany into a single empire and up to the First World War, industrial production in the country doubled, and the country came to the second place in the world in terms of the volume of products shipped by industry. Also, German goods began to successfully compete in the world market, displacing English and French even in their colonies. German machine tools, transport engineering, optics and acoustic equipment were the best in the world. And Germany was constantly competing with the United States for the first place in the number of patents and inventions.