Bilateral relations between the Kingdom of Thailand and the United States of America date back to 1818. Thailand and the United States have long been close allies and diplomatic partners. According to a 2012 Gallup public opinion poll, 60 percent of Thais approved of U.S. leadership under the Obama Administration, with 14 percent disapproving and 26 percent uncertain. As of 2013, there were 7314 international students of Thai origin studying in the United States, representing 0.9 percent of all foreigners pursuing higher education in America. According to a 2014 Global Opinion Poll, 73 percent of Thais have a favorable view of the U.S.
Question: How many percentage points did the Thai's approval of the US increase from 2012 to 2014?
Answer: 13