On an exchange rate basis, China should pass the USA in the mid-2020s.
India should pass Japan on an exchange rate basis around 2027.
China is already 20% larger than the USA in purchasing power parity terms and should be double the US economy by 2030 and India could surpass the USA in purchasing power parity terms by 2030.
The Economist magazine has a projection for the top world economies for 2018.
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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