Think tanks, also known as policy institutes, are organizations that perform policy-related research and analysis as well as advocacy on a wide range of domestic and international affairs. They are important when it comes to making informed decisions among policy makers and most of them are non-profit organizations. In the United States and Canada, they are granted tax exempt status. Every year, researchers at the University of Pennsylvania conduct an extensive analysis of think tanks around the world, publishing a report listing and ranking nearly 6,500 of them.
90.5 percent of think tanks were created after 1951 and nearly 55 percent of them are located in Europe and North America. On a country-by-country basis, the U.S. has the most by far with 1,872, followed by 512 in China and 444 in the UK. In the U.S., D.C. has the most with 397, followed by Massachusetts with 177 and California with 169.
The research also ranked global think tanks by influence. In addition to having the most of any country, the U.S. is also home to some of the world's most influential think tanks. Our of the top-10, five are U.S. based with The Brookings Institute in first place, followed by the French Institute of International Relations.