Innovations in agriculture matched innovations in industry, permitting labor to be transferred to industry while the productivity of the remaining agricultural laborers rose quickly enough to feed the growing urban population. Transcontinental railroads and fast, reliable ocean shipping further boosted world food output in the late nineteenth cuntury, making it possible to grow more basic foodstuffs in the areas best suited for this activity and get supplies to food-deficit areas in record time in emergencies. Famines, especially in what are now the high-income nations, decreased in frequency and severity. Food prices fell. Meanwhile, modern medicine, sanitation, and pharmaceutical production began to develop. All these factors helped reduce the death rate and accelerate population growth. By 1945, the population of the world was slightly less than 2.5 billion, meaning that global population grew by 0.6 percent per year between 1800 and 1945.