Some historians have compared income inequality in early 21st-century America to that of the Roman Empire in the second century, and found that modern U.S. inequality is greater. Research by historians Walter Scheidel and Steven Friesen estimates that in the Roman Empire, the top 1% controlled about 16% of the wealth, while in the United States around 2007, the top 1% controlled approximately 40% of the wealth. Additionally, the Gini coefficient—a measure of income inequality where 0 represents perfect equality and 1 represents perfect inequality—was estimated between 0.42 and 0.44 for ancient Rome. In comparison, the U.S. Gini coefficient was about 0.45 in the early 21st century, indicating slightly higher inequality.
