In 1800, the income in the United Kingdom was already several times higher than many countries, with the Industrial Revolution greatly widening the gap between high-income countries and others. Compared to industrialized nations, countries like India, China, and some African nations saw little change in income levels for most of the 19th century. The rapid development of emerging economies such as China and India in the late 20th and early 21st centuries has gradually brought these countries' income levels closer to those of high-income countries. Although global income has grown overall in the latter part of the 20th century, income disparities between high-income and low-income countries still persist. The change in global income has experienced a hugely unbalanced development, initially dominated by the income growth of developed countries driven by the Industrial Revolution, and later transformed by the rise of emerging economies, but significant global income disparities remain.