WASHINGTON, DC - JULY 31: (AFP OUT) Singer Katy Perry performs during a concert commemorating the Special Olympics with U.S. President Barack Obama, not pictured, in the State Dining Room of the White House on July 31, 2014 in Washington, D.C. Founded in 1968 by Eunice Kennedy Shriver, the Special Olympics movement has grown to more than 4.4 million athletes in 170 countries. (Photo by Andrew Harrer-Pool/Getty Images)
