A recent study reported that Massachusetts has the best economy in the United States. Cavan-Images/Shutterstock No two states' economies are the same. A recent WalletHub study ranked the economies of every state and Washington, DC, from worst to best. Massachusetts topped the list overall, while South Dakota ranked no. 1 in economic health. California's economy is the fourth largest in the world, having passed Japan's last year and trailing only the US, China, and Germany in terms of GDP. But